Synthesis of Functionalised Azabicycles via a Regiospecific Intramolecular Aldol Reaction

Synlett

Volumn 1996, Issue 9, 1996, Pages 853-855

  Stockman, Robert A ^a   Szeto, Peter ^a   Thompson, Stephen H J ^a   Hadley, Michael S ^b   Lathbury, David C ^c   Gallagher, Timothy ^a  

^a UNIVERSITY OF BRISTOL   (United Kingdom)

^b SB Pharmaceuticals   (United Kingdom)

^c SB Pharmaceuticals   (United Kingdom)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0013564350     PISSN: 09365214     EISSN: None     Source Type: Journal    
DOI: 10.1055/s-1996-5598     Document Type: Article

References (36)

1. Michael, J. P. Nat. Prod. Reports 1994, 11, 639; Howard, A. S.; Michael, J. P., in The Alkaloids; Brossi, A., Ed.; Academic Press: New York, 1986, 28, p185.
2. Michael, J. P. Nat. Prod. Reports 1994, 11, 639; Howard, A. S.; Michael, J. P., in The Alkaloids; Brossi, A., Ed.; Academic Press: New York, 1986, 28, p185.
3. For recent developments in the synthesis of indolizidines and indolizidine-containing natural products, see: (a) Cuny, G. D.; Buchwald, S. L. Syntett 1995, 519. (b) Oishi, T.; Iwakuma, T.; Hirama, M.; Itô, S. Synlett 1995, 404. (c) Takacs, J. M.; Weidner, J. J.; Newsome, P. W.; Takacs, B. E.; Chidambaram, R.; Shoemaker, R. J. Org. Chem. 1995, 60, 3473. (d) Taber, D. F.; Rahimizadeh, M.; You, K. K. J. Org. Chem. 1995, 60, 529. (e) Nukui, S.; Sodeoka, M.; Sasai, H.; Shibasaki, M. J. Org. Chem. 1995, 60, 398. (f) Pilli, R. A.; Dias, L. C.; Maldaner, A. O. J. Org. Chem. 1995, 60, 717. (g) Fleurant, A.; Saliou, C.; Célérier, J. P.; Platzer, N.; Moc, T. V.; Lhommet, G. J. Heterocycl. Chem. 1995, 32, 255. (h) Munchhof, M. J.; Meyers, A. I. J. Am. Chem. Soc. 1995, 117, 5399. (i) Leeper, F. J.; Howard, S. Tetrahedron Lett. 1995, 36, 2335. (j) Zhou, W.-S.; Xie, W.-G.; Lu, Z.-H.; Pan, X.-F. Tetrahedron Lett. 1995, 36, 1291. (k) Johnson, C. R.; Golebiowski, A.; Sundram, H.; Miller, M. W.; Dwaihy, R. L. Tetrahedron Lett. 1995, 36, 653. (l) Åhman, J.; Somfai, P. Tetrahedron Lett. 1995, 36, 303. (m) Herczegh, P.; Kovács, I.; Szilagy, L.; Sztaricskai, F.; Berecibar, A.; Riche, C.; Chiaroni, A.; Olesker, A.; Lukacs, G. Tetrahedron 1995, 51, 2969. (n) Green, D. L. C.; Kiddle, J. J.; Thompson, C. M. Tetrahedron 1995, 51, 2865. (o) Kiddle, J. J.; Green, D. L. C.; Thompson, C. M. Tetrahedron 1995, 51, 2851.
4. For recent developments in the synthesis of indolizidines and indolizidine-containing natural products, see: (a) Cuny, G. D.; Buchwald, S. L. Syntett 1995, 519. (b) Oishi, T.; Iwakuma, T.; Hirama, M.; Itô, S. Synlett 1995, 404. (c) Takacs, J. M.; Weidner, J. J.; Newsome, P. W.; Takacs, B. E.; Chidambaram, R.; Shoemaker, R. J. Org. Chem. 1995, 60, 3473. (d) Taber, D. F.; Rahimizadeh, M.; You, K. K. J. Org. Chem. 1995, 60, 529. (e) Nukui, S.; Sodeoka, M.; Sasai, H.; Shibasaki, M. J. Org. Chem. 1995, 60, 398. (f) Pilli, R. A.; Dias, L. C.; Maldaner, A. O. J. Org. Chem. 1995, 60, 717. (g) Fleurant, A.; Saliou, C.; Célérier, J. P.; Platzer, N.; Moc, T. V.; Lhommet, G. J. Heterocycl. Chem. 1995, 32, 255. (h) Munchhof, M. J.; Meyers, A. I. J. Am. Chem. Soc. 1995, 117, 5399. (i) Leeper, F. J.; Howard, S. Tetrahedron Lett. 1995, 36, 2335. (j) Zhou, W.-S.; Xie, W.-G.; Lu, Z.-H.; Pan, X.-F. Tetrahedron Lett. 1995, 36, 1291. (k) Johnson, C. R.; Golebiowski, A.; Sundram, H.; Miller, M. W.; Dwaihy, R. L. Tetrahedron Lett. 1995, 36, 653. (l) Åhman, J.; Somfai, P. Tetrahedron Lett. 1995, 36, 303. (m) Herczegh, P.; Kovács, I.; Szilagy, L.; Sztaricskai, F.; Berecibar, A.; Riche, C.; Chiaroni, A.; Olesker, A.; Lukacs, G. Tetrahedron 1995, 51, 2969. (n) Green, D. L. C.; Kiddle, J. J.; Thompson, C. M. Tetrahedron 1995, 51, 2865. (o) Kiddle, J. J.; Green, D. L. C.; Thompson, C. M. Tetrahedron 1995, 51, 2851.
5. For recent developments in the synthesis of indolizidines and indolizidine-containing natural products, see: (a) Cuny, G. D.; Buchwald, S. L. Syntett 1995, 519. (b) Oishi, T.; Iwakuma, T.; Hirama, M.; Itô, S. Synlett 1995, 404. (c) Takacs, J. M.; Weidner, J. J.; Newsome, P. W.; Takacs, B. E.; Chidambaram, R.; Shoemaker, R. J. Org. Chem. 1995, 60, 3473. (d) Taber, D. F.; Rahimizadeh, M.; You, K. K. J. Org. Chem. 1995, 60, 529. (e) Nukui, S.; Sodeoka, M.; Sasai, H.; Shibasaki, M. J. Org. Chem. 1995, 60, 398. (f) Pilli, R. A.; Dias, L. C.; Maldaner, A. O. J. Org. Chem. 1995, 60, 717. (g) Fleurant, A.; Saliou, C.; Célérier, J. P.; Platzer, N.; Moc, T. V.; Lhommet, G. J. Heterocycl. Chem. 1995, 32, 255. (h) Munchhof, M. J.; Meyers, A. I. J. Am. Chem. Soc. 1995, 117, 5399. (i) Leeper, F. J.; Howard, S. Tetrahedron Lett. 1995, 36, 2335. (j) Zhou, W.-S.; Xie, W.-G.; Lu, Z.-H.; Pan, X.-F. Tetrahedron Lett. 1995, 36, 1291. (k) Johnson, C. R.; Golebiowski, A.; Sundram, H.; Miller, M. W.; Dwaihy, R. L. Tetrahedron Lett. 1995, 36, 653. (l) Åhman, J.; Somfai, P. Tetrahedron Lett. 1995, 36, 303. (m) Herczegh, P.; Kovács, I.; Szilagy, L.; Sztaricskai, F.; Berecibar, A.; Riche, C.; Chiaroni, A.; Olesker, A.; Lukacs, G. Tetrahedron 1995, 51, 2969. (n) Green, D. L. C.; Kiddle, J. J.; Thompson, C. M. Tetrahedron 1995, 51, 2865. (o) Kiddle, J. J.; Green, D. L. C.; Thompson, C. M. Tetrahedron 1995, 51, 2851.
6. For recent developments in the synthesis of indolizidines and indolizidine-containing natural products, see: (a) Cuny, G. D.; Buchwald, S. L. Syntett 1995, 519. (b) Oishi, T.; Iwakuma, T.; Hirama, M.; Itô, S. Synlett 1995, 404. (c) Takacs, J. M.; Weidner, J. J.; Newsome, P. W.; Takacs, B. E.; Chidambaram, R.; Shoemaker, R. J. Org. Chem. 1995, 60, 3473. (d) Taber, D. F.; Rahimizadeh, M.; You, K. K. J. Org. Chem. 1995, 60, 529. (e) Nukui, S.; Sodeoka, M.; Sasai, H.; Shibasaki, M. J. Org. Chem. 1995, 60, 398. (f) Pilli, R. A.; Dias, L. C.; Maldaner, A. O. J. Org. Chem. 1995, 60, 717. (g) Fleurant, A.; Saliou, C.; Célérier, J. P.; Platzer, N.; Moc, T. V.; Lhommet, G. J. Heterocycl. Chem. 1995, 32, 255. (h) Munchhof, M. J.; Meyers, A. I. J. Am. Chem. Soc. 1995, 117, 5399. (i) Leeper, F. J.; Howard, S. Tetrahedron Lett. 1995, 36, 2335. (j) Zhou, W.-S.; Xie, W.-G.; Lu, Z.-H.; Pan, X.-F. Tetrahedron Lett. 1995, 36, 1291. (k) Johnson, C. R.; Golebiowski, A.; Sundram, H.; Miller, M. W.; Dwaihy, R. L. Tetrahedron Lett. 1995, 36, 653. (l) Åhman, J.; Somfai, P. Tetrahedron Lett. 1995, 36, 303. (m) Herczegh, P.; Kovács, I.; Szilagy, L.; Sztaricskai, F.; Berecibar, A.; Riche, C.; Chiaroni, A.; Olesker, A.; Lukacs, G. Tetrahedron 1995, 51, 2969. (n) Green, D. L. C.; Kiddle, J. J.; Thompson, C. M. Tetrahedron 1995, 51, 2865. (o) Kiddle, J. J.; Green, D. L. C.; Thompson, C. M. Tetrahedron 1995, 51, 2851.
7. For recent developments in the synthesis of indolizidines and indolizidine-containing natural products, see: (a) Cuny, G. D.; Buchwald, S. L. Syntett 1995, 519. (b) Oishi, T.; Iwakuma, T.; Hirama, M.; Itô, S. Synlett 1995, 404. (c) Takacs, J. M.; Weidner, J. J.; Newsome, P. W.; Takacs, B. E.; Chidambaram, R.; Shoemaker, R. J. Org. Chem. 1995, 60, 3473. (d) Taber, D. F.; Rahimizadeh, M.; You, K. K. J. Org. Chem. 1995, 60, 529. (e) Nukui, S.; Sodeoka, M.; Sasai, H.; Shibasaki, M. J. Org. Chem. 1995, 60, 398. (f) Pilli, R. A.; Dias, L. C.; Maldaner, A. O. J. Org. Chem. 1995, 60, 717. (g) Fleurant, A.; Saliou, C.; Célérier, J. P.; Platzer, N.; Moc, T. V.; Lhommet, G. J. Heterocycl. Chem. 1995, 32, 255. (h) Munchhof, M. J.; Meyers, A. I. J. Am. Chem. Soc. 1995, 117, 5399. (i) Leeper, F. J.; Howard, S. Tetrahedron Lett. 1995, 36, 2335. (j) Zhou, W.-S.; Xie, W.-G.; Lu, Z.-H.; Pan, X.-F. Tetrahedron Lett. 1995, 36, 1291. (k) Johnson, C. R.; Golebiowski, A.; Sundram, H.; Miller, M. W.; Dwaihy, R. L. Tetrahedron Lett. 1995, 36, 653. (l) Åhman, J.; Somfai, P. Tetrahedron Lett. 1995, 36, 303. (m) Herczegh, P.; Kovács, I.; Szilagy, L.; Sztaricskai, F.; Berecibar, A.; Riche, C.; Chiaroni, A.; Olesker, A.; Lukacs, G. Tetrahedron 1995, 51, 2969. (n) Green, D. L. C.; Kiddle, J. J.; Thompson, C. M. Tetrahedron 1995, 51, 2865. (o) Kiddle, J. J.; Green, D. L. C.; Thompson, C. M. Tetrahedron 1995, 51, 2851.
8. For recent developments in the synthesis of indolizidines and indolizidine-containing natural products, see: (a) Cuny, G. D.; Buchwald, S. L. Syntett 1995, 519. (b) Oishi, T.; Iwakuma, T.; Hirama, M.; Itô, S. Synlett 1995, 404. (c) Takacs, J. M.; Weidner, J. J.; Newsome, P. W.; Takacs, B. E.; Chidambaram, R.; Shoemaker, R. J. Org. Chem. 1995, 60, 3473. (d) Taber, D. F.; Rahimizadeh, M.; You, K. K. J. Org. Chem. 1995, 60, 529. (e) Nukui, S.; Sodeoka, M.; Sasai, H.; Shibasaki, M. J. Org. Chem. 1995, 60, 398. (f) Pilli, R. A.; Dias, L. C.; Maldaner, A. O. J. Org. Chem. 1995, 60, 717. (g) Fleurant, A.; Saliou, C.; Célérier, J. P.; Platzer, N.; Moc, T. V.; Lhommet, G. J. Heterocycl. Chem. 1995, 32, 255. (h) Munchhof, M. J.; Meyers, A. I. J. Am. Chem. Soc. 1995, 117, 5399. (i) Leeper, F. J.; Howard, S. Tetrahedron Lett. 1995, 36, 2335. (j) Zhou, W.-S.; Xie, W.-G.; Lu, Z.-H.; Pan, X.-F. Tetrahedron Lett. 1995, 36, 1291. (k) Johnson, C. R.; Golebiowski, A.; Sundram, H.; Miller, M. W.; Dwaihy, R. L. Tetrahedron Lett. 1995, 36, 653. (l) Åhman, J.; Somfai, P. Tetrahedron Lett. 1995, 36, 303. (m) Herczegh, P.; Kovács, I.; Szilagy, L.; Sztaricskai, F.; Berecibar, A.; Riche, C.; Chiaroni, A.; Olesker, A.; Lukacs, G. Tetrahedron 1995, 51, 2969. (n) Green, D. L. C.; Kiddle, J. J.; Thompson, C. M. Tetrahedron 1995, 51, 2865. (o) Kiddle, J. J.; Green, D. L. C.; Thompson, C. M. Tetrahedron 1995, 51, 2851.
9. For recent developments in the synthesis of indolizidines and indolizidine-containing natural products, see: (a) Cuny, G. D.; Buchwald, S. L. Syntett 1995, 519. (b) Oishi, T.; Iwakuma, T.; Hirama, M.; Itô, S. Synlett 1995, 404. (c) Takacs, J. M.; Weidner, J. J.; Newsome, P. W.; Takacs, B. E.; Chidambaram, R.; Shoemaker, R. J. Org. Chem. 1995, 60, 3473. (d) Taber, D. F.; Rahimizadeh, M.; You, K. K. J. Org. Chem. 1995, 60, 529. (e) Nukui, S.; Sodeoka, M.; Sasai, H.; Shibasaki, M. J. Org. Chem. 1995, 60, 398. (f) Pilli, R. A.; Dias, L. C.; Maldaner, A. O. J. Org. Chem. 1995, 60, 717. (g) Fleurant, A.; Saliou, C.; Célérier, J. P.; Platzer, N.; Moc, T. V.; Lhommet, G. J. Heterocycl. Chem. 1995, 32, 255. (h) Munchhof, M. J.; Meyers, A. I. J. Am. Chem. Soc. 1995, 117, 5399. (i) Leeper, F. J.; Howard, S. Tetrahedron Lett. 1995, 36, 2335. (j) Zhou, W.-S.; Xie, W.-G.; Lu, Z.-H.; Pan, X.-F. Tetrahedron Lett. 1995, 36, 1291. (k) Johnson, C. R.; Golebiowski, A.; Sundram, H.; Miller, M. W.; Dwaihy, R. L. Tetrahedron Lett. 1995, 36, 653. (l) Åhman, J.; Somfai, P. Tetrahedron Lett. 1995, 36, 303. (m) Herczegh, P.; Kovács, I.; Szilagy, L.; Sztaricskai, F.; Berecibar, A.; Riche, C.; Chiaroni, A.; Olesker, A.; Lukacs, G. Tetrahedron 1995, 51, 2969. (n) Green, D. L. C.; Kiddle, J. J.; Thompson, C. M. Tetrahedron 1995, 51, 2865. (o) Kiddle, J. J.; Green, D. L. C.; Thompson, C. M. Tetrahedron 1995, 51, 2851.
10. For recent developments in the synthesis of indolizidines and indolizidine-containing natural products, see: (a) Cuny, G. D.; Buchwald, S. L. Syntett 1995, 519. (b) Oishi, T.; Iwakuma, T.; Hirama, M.; Itô, S. Synlett 1995, 404. (c) Takacs, J. M.; Weidner, J. J.; Newsome, P. W.; Takacs, B. E.; Chidambaram, R.; Shoemaker, R. J. Org. Chem. 1995, 60, 3473. (d) Taber, D. F.; Rahimizadeh, M.; You, K. K. J. Org. Chem. 1995, 60, 529. (e) Nukui, S.; Sodeoka, M.; Sasai, H.; Shibasaki, M. J. Org. Chem. 1995, 60, 398. (f) Pilli, R. A.; Dias, L. C.; Maldaner, A. O. J. Org. Chem. 1995, 60, 717. (g) Fleurant, A.; Saliou, C.; Célérier, J. P.; Platzer, N.; Moc, T. V.; Lhommet, G. J. Heterocycl. Chem. 1995, 32, 255. (h) Munchhof, M. J.; Meyers, A. I. J. Am. Chem. Soc. 1995, 117, 5399. (i) Leeper, F. J.; Howard, S. Tetrahedron Lett. 1995, 36, 2335. (j) Zhou, W.-S.; Xie, W.-G.; Lu, Z.-H.; Pan, X.-F. Tetrahedron Lett. 1995, 36, 1291. (k) Johnson, C. R.; Golebiowski, A.; Sundram, H.; Miller, M. W.; Dwaihy, R. L. Tetrahedron Lett. 1995, 36, 653. (l) Åhman, J.; Somfai, P. Tetrahedron Lett. 1995, 36, 303. (m) Herczegh, P.; Kovács, I.; Szilagy, L.; Sztaricskai, F.; Berecibar, A.; Riche, C.; Chiaroni, A.; Olesker, A.; Lukacs, G. Tetrahedron 1995, 51, 2969. (n) Green, D. L. C.; Kiddle, J. J.; Thompson, C. M. Tetrahedron 1995, 51, 2865. (o) Kiddle, J. J.; Green, D. L. C.; Thompson, C. M. Tetrahedron 1995, 51, 2851.
11. For recent developments in the synthesis of indolizidines and indolizidine-containing natural products, see: (a) Cuny, G. D.; Buchwald, S. L. Syntett 1995, 519. (b) Oishi, T.; Iwakuma, T.; Hirama, M.; Itô, S. Synlett 1995, 404. (c) Takacs, J. M.; Weidner, J. J.; Newsome, P. W.; Takacs, B. E.; Chidambaram, R.; Shoemaker, R. J. Org. Chem. 1995, 60, 3473. (d) Taber, D. F.; Rahimizadeh, M.; You, K. K. J. Org. Chem. 1995, 60, 529. (e) Nukui, S.; Sodeoka, M.; Sasai, H.; Shibasaki, M. J. Org. Chem. 1995, 60, 398. (f) Pilli, R. A.; Dias, L. C.; Maldaner, A. O. J. Org. Chem. 1995, 60, 717. (g) Fleurant, A.; Saliou, C.; Célérier, J. P.; Platzer, N.; Moc, T. V.; Lhommet, G. J. Heterocycl. Chem. 1995, 32, 255. (h) Munchhof, M. J.; Meyers, A. I. J. Am. Chem. Soc. 1995, 117, 5399. (i) Leeper, F. J.; Howard, S. Tetrahedron Lett. 1995, 36, 2335. (j) Zhou, W.-S.; Xie, W.-G.; Lu, Z.-H.; Pan, X.-F. Tetrahedron Lett. 1995, 36, 1291. (k) Johnson, C. R.; Golebiowski, A.; Sundram, H.; Miller, M. W.; Dwaihy, R. L. Tetrahedron Lett. 1995, 36, 653. (l) Åhman, J.; Somfai, P. Tetrahedron Lett. 1995, 36, 303. (m) Herczegh, P.; Kovács, I.; Szilagy, L.; Sztaricskai, F.; Berecibar, A.; Riche, C.; Chiaroni, A.; Olesker, A.; Lukacs, G. Tetrahedron 1995, 51, 2969. (n) Green, D. L. C.; Kiddle, J. J.; Thompson, C. M. Tetrahedron 1995, 51, 2865. (o) Kiddle, J. J.; Green, D. L. C.; Thompson, C. M. Tetrahedron 1995, 51, 2851.
12. For recent developments in the synthesis of indolizidines and indolizidine-containing natural products, see: (a) Cuny, G. D.; Buchwald, S. L. Syntett 1995, 519. (b) Oishi, T.; Iwakuma, T.; Hirama, M.; Itô, S. Synlett 1995, 404. (c) Takacs, J. M.; Weidner, J. J.; Newsome, P. W.; Takacs, B. E.; Chidambaram, R.; Shoemaker, R. J. Org. Chem. 1995, 60, 3473. (d) Taber, D. F.; Rahimizadeh, M.; You, K. K. J. Org. Chem. 1995, 60, 529. (e) Nukui, S.; Sodeoka, M.; Sasai, H.; Shibasaki, M. J. Org. Chem. 1995, 60, 398. (f) Pilli, R. A.; Dias, L. C.; Maldaner, A. O. J. Org. Chem. 1995, 60, 717. (g) Fleurant, A.; Saliou, C.; Célérier, J. P.; Platzer, N.; Moc, T. V.; Lhommet, G. J. Heterocycl. Chem. 1995, 32, 255. (h) Munchhof, M. J.; Meyers, A. I. J. Am. Chem. Soc. 1995, 117, 5399. (i) Leeper, F. J.; Howard, S. Tetrahedron Lett. 1995, 36, 2335. (j) Zhou, W.-S.; Xie, W.-G.; Lu, Z.-H.; Pan, X.-F. Tetrahedron Lett. 1995, 36, 1291. (k) Johnson, C. R.; Golebiowski, A.; Sundram, H.; Miller, M. W.; Dwaihy, R. L. Tetrahedron Lett. 1995, 36, 653. (l) Åhman, J.; Somfai, P. Tetrahedron Lett. 1995, 36, 303. (m) Herczegh, P.; Kovács, I.; Szilagy, L.; Sztaricskai, F.; Berecibar, A.; Riche, C.; Chiaroni, A.; Olesker, A.; Lukacs, G. Tetrahedron 1995, 51, 2969. (n) Green, D. L. C.; Kiddle, J. J.; Thompson, C. M. Tetrahedron 1995, 51, 2865. (o) Kiddle, J. J.; Green, D. L. C.; Thompson, C. M. Tetrahedron 1995, 51, 2851.
13. For recent developments in the synthesis of indolizidines and indolizidine-containing natural products, see: (a) Cuny, G. D.; Buchwald, S. L. Syntett 1995, 519. (b) Oishi, T.; Iwakuma, T.; Hirama, M.; Itô, S. Synlett 1995, 404. (c) Takacs, J. M.; Weidner, J. J.; Newsome, P. W.; Takacs, B. E.; Chidambaram, R.; Shoemaker, R. J. Org. Chem. 1995, 60, 3473. (d) Taber, D. F.; Rahimizadeh, M.; You, K. K. J. Org. Chem. 1995, 60, 529. (e) Nukui, S.; Sodeoka, M.; Sasai, H.; Shibasaki, M. J. Org. Chem. 1995, 60, 398. (f) Pilli, R. A.; Dias, L. C.; Maldaner, A. O. J. Org. Chem. 1995, 60, 717. (g) Fleurant, A.; Saliou, C.; Célérier, J. P.; Platzer, N.; Moc, T. V.; Lhommet, G. J. Heterocycl. Chem. 1995, 32, 255. (h) Munchhof, M. J.; Meyers, A. I. J. Am. Chem. Soc. 1995, 117, 5399. (i) Leeper, F. J.; Howard, S. Tetrahedron Lett. 1995, 36, 2335. (j) Zhou, W.-S.; Xie, W.-G.; Lu, Z.-H.; Pan, X.-F. Tetrahedron Lett. 1995, 36, 1291. (k) Johnson, C. R.; Golebiowski, A.; Sundram, H.; Miller, M. W.; Dwaihy, R. L. Tetrahedron Lett. 1995, 36, 653. (l) Åhman, J.; Somfai, P. Tetrahedron Lett. 1995, 36, 303. (m) Herczegh, P.; Kovács, I.; Szilagy, L.; Sztaricskai, F.; Berecibar, A.; Riche, C.; Chiaroni, A.; Olesker, A.; Lukacs, G. Tetrahedron 1995, 51, 2969. (n) Green, D. L. C.; Kiddle, J. J.; Thompson, C. M. Tetrahedron 1995, 51, 2865. (o) Kiddle, J. J.; Green, D. L. C.; Thompson, C. M. Tetrahedron 1995, 51, 2851.
14. For recent developments in the synthesis of indolizidines and indolizidine-containing natural products, see: (a) Cuny, G. D.; Buchwald, S. L. Syntett 1995, 519. (b) Oishi, T.; Iwakuma, T.; Hirama, M.; Itô, S. Synlett 1995, 404. (c) Takacs, J. M.; Weidner, J. J.; Newsome, P. W.; Takacs, B. E.; Chidambaram, R.; Shoemaker, R. J. Org. Chem. 1995, 60, 3473. (d) Taber, D. F.; Rahimizadeh, M.; You, K. K. J. Org. Chem. 1995, 60, 529. (e) Nukui, S.; Sodeoka, M.; Sasai, H.; Shibasaki, M. J. Org. Chem. 1995, 60, 398. (f) Pilli, R. A.; Dias, L. C.; Maldaner, A. O. J. Org. Chem. 1995, 60, 717. (g) Fleurant, A.; Saliou, C.; Célérier, J. P.; Platzer, N.; Moc, T. V.; Lhommet, G. J. Heterocycl. Chem. 1995, 32, 255. (h) Munchhof, M. J.; Meyers, A. I. J. Am. Chem. Soc. 1995, 117, 5399. (i) Leeper, F. J.; Howard, S. Tetrahedron Lett. 1995, 36, 2335. (j) Zhou, W.-S.; Xie, W.-G.; Lu, Z.-H.; Pan, X.-F. Tetrahedron Lett. 1995, 36, 1291. (k) Johnson, C. R.; Golebiowski, A.; Sundram, H.; Miller, M. W.; Dwaihy, R. L. Tetrahedron Lett. 1995, 36, 653. (l) Åhman, J.; Somfai, P. Tetrahedron Lett. 1995, 36, 303. (m) Herczegh, P.; Kovács, I.; Szilagy, L.; Sztaricskai, F.; Berecibar, A.; Riche, C.; Chiaroni, A.; Olesker, A.; Lukacs, G. Tetrahedron 1995, 51, 2969. (n) Green, D. L. C.; Kiddle, J. J.; Thompson, C. M. Tetrahedron 1995, 51, 2865. (o) Kiddle, J. J.; Green, D. L. C.; Thompson, C. M. Tetrahedron 1995, 51, 2851.
15. For recent developments in the synthesis of indolizidines and indolizidine-containing natural products, see: (a) Cuny, G. D.; Buchwald, S. L. Syntett 1995, 519. (b) Oishi, T.; Iwakuma, T.; Hirama, M.; Itô, S. Synlett 1995, 404. (c) Takacs, J. M.; Weidner, J. J.; Newsome, P. W.; Takacs, B. E.; Chidambaram, R.; Shoemaker, R. J. Org. Chem. 1995, 60, 3473. (d) Taber, D. F.; Rahimizadeh, M.; You, K. K. J. Org. Chem. 1995, 60, 529. (e) Nukui, S.; Sodeoka, M.; Sasai, H.; Shibasaki, M. J. Org. Chem. 1995, 60, 398. (f) Pilli, R. A.; Dias, L. C.; Maldaner, A. O. J. Org. Chem. 1995, 60, 717. (g) Fleurant, A.; Saliou, C.; Célérier, J. P.; Platzer, N.; Moc, T. V.; Lhommet, G. J. Heterocycl. Chem. 1995, 32, 255. (h) Munchhof, M. J.; Meyers, A. I. J. Am. Chem. Soc. 1995, 117, 5399. (i) Leeper, F. J.; Howard, S. Tetrahedron Lett. 1995, 36, 2335. (j) Zhou, W.-S.; Xie, W.-G.; Lu, Z.-H.; Pan, X.-F. Tetrahedron Lett. 1995, 36, 1291. (k) Johnson, C. R.; Golebiowski, A.; Sundram, H.; Miller, M. W.; Dwaihy, R. L. Tetrahedron Lett. 1995, 36, 653. (l) Åhman, J.; Somfai, P. Tetrahedron Lett. 1995, 36, 303. (m) Herczegh, P.; Kovács, I.; Szilagy, L.; Sztaricskai, F.; Berecibar, A.; Riche, C.; Chiaroni, A.; Olesker, A.; Lukacs, G. Tetrahedron 1995, 51, 2969. (n) Green, D. L. C.; Kiddle, J. J.; Thompson, C. M. Tetrahedron 1995, 51, 2865. (o) Kiddle, J. J.; Green, D. L. C.; Thompson, C. M. Tetrahedron 1995, 51, 2851.
16. For recent developments in the synthesis of indolizidines and indolizidine-containing natural products, see: (a) Cuny, G. D.; Buchwald, S. L. Syntett 1995, 519. (b) Oishi, T.; Iwakuma, T.; Hirama, M.; Itô, S. Synlett 1995, 404. (c) Takacs, J. M.; Weidner, J. J.; Newsome, P. W.; Takacs, B. E.; Chidambaram, R.; Shoemaker, R. J. Org. Chem. 1995, 60, 3473. (d) Taber, D. F.; Rahimizadeh, M.; You, K. K. J. Org. Chem. 1995, 60, 529. (e) Nukui, S.; Sodeoka, M.; Sasai, H.; Shibasaki, M. J. Org. Chem. 1995, 60, 398. (f) Pilli, R. A.; Dias, L. C.; Maldaner, A. O. J. Org. Chem. 1995, 60, 717. (g) Fleurant, A.; Saliou, C.; Célérier, J. P.; Platzer, N.; Moc, T. V.; Lhommet, G. J. Heterocycl. Chem. 1995, 32, 255. (h) Munchhof, M. J.; Meyers, A. I. J. Am. Chem. Soc. 1995, 117, 5399. (i) Leeper, F. J.; Howard, S. Tetrahedron Lett. 1995, 36, 2335. (j) Zhou, W.-S.; Xie, W.-G.; Lu, Z.-H.; Pan, X.-F. Tetrahedron Lett. 1995, 36, 1291. (k) Johnson, C. R.; Golebiowski, A.; Sundram, H.; Miller, M. W.; Dwaihy, R. L. Tetrahedron Lett. 1995, 36, 653. (l) Åhman, J.; Somfai, P. Tetrahedron Lett. 1995, 36, 303. (m) Herczegh, P.; Kovács, I.; Szilagy, L.; Sztaricskai, F.; Berecibar, A.; Riche, C.; Chiaroni, A.; Olesker, A.; Lukacs, G. Tetrahedron 1995, 51, 2969. (n) Green, D. L. C.; Kiddle, J. J.; Thompson, C. M. Tetrahedron 1995, 51, 2865. (o) Kiddle, J. J.; Green, D. L. C.; Thompson, C. M. Tetrahedron 1995, 51, 2851.
17. For recent developments in the synthesis of indolizidines and indolizidine-containing natural products, see: (a) Cuny, G. D.; Buchwald, S. L. Syntett 1995, 519. (b) Oishi, T.; Iwakuma, T.; Hirama, M.; Itô, S. Synlett 1995, 404. (c) Takacs, J. M.; Weidner, J. J.; Newsome, P. W.; Takacs, B. E.; Chidambaram, R.; Shoemaker, R. J. Org. Chem. 1995, 60, 3473. (d) Taber, D. F.; Rahimizadeh, M.; You, K. K. J. Org. Chem. 1995, 60, 529. (e) Nukui, S.; Sodeoka, M.; Sasai, H.; Shibasaki, M. J. Org. Chem. 1995, 60, 398. (f) Pilli, R. A.; Dias, L. C.; Maldaner, A. O. J. Org. Chem. 1995, 60, 717. (g) Fleurant, A.; Saliou, C.; Célérier, J. P.; Platzer, N.; Moc, T. V.; Lhommet, G. J. Heterocycl. Chem. 1995, 32, 255. (h) Munchhof, M. J.; Meyers, A. I. J. Am. Chem. Soc. 1995, 117, 5399. (i) Leeper, F. J.; Howard, S. Tetrahedron Lett. 1995, 36, 2335. (j) Zhou, W.-S.; Xie, W.-G.; Lu, Z.-H.; Pan, X.-F. Tetrahedron Lett. 1995, 36, 1291. (k) Johnson, C. R.; Golebiowski, A.; Sundram, H.; Miller, M. W.; Dwaihy, R. L. Tetrahedron Lett. 1995, 36, 653. (l) Åhman, J.; Somfai, P. Tetrahedron Lett. 1995, 36, 303. (m) Herczegh, P.; Kovács, I.; Szilagy, L.; Sztaricskai, F.; Berecibar, A.; Riche, C.; Chiaroni, A.; Olesker, A.; Lukacs, G. Tetrahedron 1995, 51, 2969. (n) Green, D. L. C.; Kiddle, J. J.; Thompson, C. M. Tetrahedron 1995, 51, 2865. (o) Kiddle, J. J.; Green, D. L. C.; Thompson, C. M. Tetrahedron 1995, 51, 2851.
18. Szeto, P.; Lathbury, D. C.; Gallagher, T. Tetrahedron Lett. 1995, 36, 6957.
19. For examples of structurally similar aldehyde/ketone-based intramolecular aldol reactions, see: (a) Danishefsky, S.; Zamboni, R.; Kahn, M.; Etheredge, S. J. J. Am. Chem. Soc. 1981, 103, 3460. (b) Bal, S. A.; Marfat, A.; Helquist, P. J. Org. Chem. 1982, 47, 5045. (c) Heathcock, C. H.; Kleinman, E. F.; Binkley, E. S. J. Am. Chem. Soc. 1982, 104, 1054. (d) Duthaler, R. O.; Maienfisch, P. Helv. Chim. Acta 1984, 67, 856. (e) Jones, P. S.; Ley, S. V.; Simpkins, N. S.; Whittle, A. J. Tetrahedron 1986, 42, 6519. (f) Agami, G.; Platzer, N.; Puchot, C.; Sevestre, H. Tetrahedron 1987, 43, 1091 and references therein. (g) Kawamata, T.; Harimaya, K.; Inayama, S. Bull. Chem. Soc. Jp. 1988, 61, 3770. (h) Tori, M.; Furuta, H.; Asakawa, Y. J. Chem. Soc., Perkin Trans. 1 1991, 1919. (i) Gwaltney, S. L.; Sakata, S. T.; Shea, K. J. Tetrahedron Lett. 1995, 36, 7177. (j) La Clair, J. J.; Lansbury, P. T.; Zhi, B. X.; Hoogsteen, K. J. Org. Chem. 1995, 60, 4822.
20. For examples of structurally similar aldehyde/ketone-based intramolecular aldol reactions, see: (a) Danishefsky, S.; Zamboni, R.; Kahn, M.; Etheredge, S. J. J. Am. Chem. Soc. 1981, 103, 3460. (b) Bal, S. A.; Marfat, A.; Helquist, P. J. Org. Chem. 1982, 47, 5045. (c) Heathcock, C. H.; Kleinman, E. F.; Binkley, E. S. J. Am. Chem. Soc. 1982, 104, 1054. (d) Duthaler, R. O.; Maienfisch, P. Helv. Chim. Acta 1984, 67, 856. (e) Jones, P. S.; Ley, S. V.; Simpkins, N. S.; Whittle, A. J. Tetrahedron 1986, 42, 6519. (f) Agami, G.; Platzer, N.; Puchot, C.; Sevestre, H. Tetrahedron 1987, 43, 1091 and references therein. (g) Kawamata, T.; Harimaya, K.; Inayama, S. Bull. Chem. Soc. Jp. 1988, 61, 3770. (h) Tori, M.; Furuta, H.; Asakawa, Y. J. Chem. Soc., Perkin Trans. 1 1991, 1919. (i) Gwaltney, S. L.; Sakata, S. T.; Shea, K. J. Tetrahedron Lett. 1995, 36, 7177. (j) La Clair, J. J.; Lansbury, P. T.; Zhi, B. X.; Hoogsteen, K. J. Org. Chem. 1995, 60, 4822.
21. For examples of structurally similar aldehyde/ketone-based intramolecular aldol reactions, see: (a) Danishefsky, S.; Zamboni, R.; Kahn, M.; Etheredge, S. J. J. Am. Chem. Soc. 1981, 103, 3460. (b) Bal, S. A.; Marfat, A.; Helquist, P. J. Org. Chem. 1982, 47, 5045. (c) Heathcock, C. H.; Kleinman, E. F.; Binkley, E. S. J. Am. Chem. Soc. 1982, 104, 1054. (d) Duthaler, R. O.; Maienfisch, P. Helv. Chim. Acta 1984, 67, 856. (e) Jones, P. S.; Ley, S. V.; Simpkins, N. S.; Whittle, A. J. Tetrahedron 1986, 42, 6519. (f) Agami, G.; Platzer, N.; Puchot, C.; Sevestre, H. Tetrahedron 1987, 43, 1091 and references therein. (g) Kawamata, T.; Harimaya, K.; Inayama, S. Bull. Chem. Soc. Jp. 1988, 61, 3770. (h) Tori, M.; Furuta, H.; Asakawa, Y. J. Chem. Soc., Perkin Trans. 1 1991, 1919. (i) Gwaltney, S. L.; Sakata, S. T.; Shea, K. J. Tetrahedron Lett. 1995, 36, 7177. (j) La Clair, J. J.; Lansbury, P. T.; Zhi, B. X.; Hoogsteen, K. J. Org. Chem. 1995, 60, 4822.
22. For examples of structurally similar aldehyde/ketone-based intramolecular aldol reactions, see: (a) Danishefsky, S.; Zamboni, R.; Kahn, M.; Etheredge, S. J. J. Am. Chem. Soc. 1981, 103, 3460. (b) Bal, S. A.; Marfat, A.; Helquist, P. J. Org. Chem. 1982, 47, 5045. (c) Heathcock, C. H.; Kleinman, E. F.; Binkley, E. S. J. Am. Chem. Soc. 1982, 104, 1054. (d) Duthaler, R. O.; Maienfisch, P. Helv. Chim. Acta 1984, 67, 856. (e) Jones, P. S.; Ley, S. V.; Simpkins, N. S.; Whittle, A. J. Tetrahedron 1986, 42, 6519. (f) Agami, G.; Platzer, N.; Puchot, C.; Sevestre, H. Tetrahedron 1987, 43, 1091 and references therein. (g) Kawamata, T.; Harimaya, K.; Inayama, S. Bull. Chem. Soc. Jp. 1988, 61, 3770. (h) Tori, M.; Furuta, H.; Asakawa, Y. J. Chem. Soc., Perkin Trans. 1 1991, 1919. (i) Gwaltney, S. L.; Sakata, S. T.; Shea, K. J. Tetrahedron Lett. 1995, 36, 7177. (j) La Clair, J. J.; Lansbury, P. T.; Zhi, B. X.; Hoogsteen, K. J. Org. Chem. 1995, 60, 4822.
23. For examples of structurally similar aldehyde/ketone-based intramolecular aldol reactions, see: (a) Danishefsky, S.; Zamboni, R.; Kahn, M.; Etheredge, S. J. J. Am. Chem. Soc. 1981, 103, 3460. (b) Bal, S. A.; Marfat, A.; Helquist, P. J. Org. Chem. 1982, 47, 5045. (c) Heathcock, C. H.; Kleinman, E. F.; Binkley, E. S. J. Am. Chem. Soc. 1982, 104, 1054. (d) Duthaler, R. O.; Maienfisch, P. Helv. Chim. Acta 1984, 67, 856. (e) Jones, P. S.; Ley, S. V.; Simpkins, N. S.; Whittle, A. J. Tetrahedron 1986, 42, 6519. (f) Agami, G.; Platzer, N.; Puchot, C.; Sevestre, H. Tetrahedron 1987, 43, 1091 and references therein. (g) Kawamata, T.; Harimaya, K.; Inayama, S. Bull. Chem. Soc. Jp. 1988, 61, 3770. (h) Tori, M.; Furuta, H.; Asakawa, Y. J. Chem. Soc., Perkin Trans. 1 1991, 1919. (i) Gwaltney, S. L.; Sakata, S. T.; Shea, K. J. Tetrahedron Lett. 1995, 36, 7177. (j) La Clair, J. J.; Lansbury, P. T.; Zhi, B. X.; Hoogsteen, K. J. Org. Chem. 1995, 60, 4822.
24. For examples of structurally similar aldehyde/ketone-based intramolecular aldol reactions, see: (a) Danishefsky, S.; Zamboni, R.; Kahn, M.; Etheredge, S. J. J. Am. Chem. Soc. 1981, 103, 3460. (b) Bal, S. A.; Marfat, A.; Helquist, P. J. Org. Chem. 1982, 47, 5045. (c) Heathcock, C. H.; Kleinman, E. F.; Binkley, E. S. J. Am. Chem. Soc. 1982, 104, 1054. (d) Duthaler, R. O.; Maienfisch, P. Helv. Chim. Acta 1984, 67, 856. (e) Jones, P. S.; Ley, S. V.; Simpkins, N. S.; Whittle, A. J. Tetrahedron 1986, 42, 6519. (f) Agami, G.; Platzer, N.; Puchot, C.; Sevestre, H. Tetrahedron 1987, 43, 1091 and references therein. (g) Kawamata, T.; Harimaya, K.; Inayama, S. Bull. Chem. Soc. Jp. 1988, 61, 3770. (h) Tori, M.; Furuta, H.; Asakawa, Y. J. Chem. Soc., Perkin Trans. 1 1991, 1919. (i) Gwaltney, S. L.; Sakata, S. T.; Shea, K. J. Tetrahedron Lett. 1995, 36, 7177. (j) La Clair, J. J.; Lansbury, P. T.; Zhi, B. X.; Hoogsteen, K. J. Org. Chem. 1995, 60, 4822.
25. For examples of structurally similar aldehyde/ketone-based intramolecular aldol reactions, see: (a) Danishefsky, S.; Zamboni, R.; Kahn, M.; Etheredge, S. J. J. Am. Chem. Soc. 1981, 103, 3460. (b) Bal, S. A.; Marfat, A.; Helquist, P. J. Org. Chem. 1982, 47, 5045. (c) Heathcock, C. H.; Kleinman, E. F.; Binkley, E. S. J. Am. Chem. Soc. 1982, 104, 1054. (d) Duthaler, R. O.; Maienfisch, P. Helv. Chim. Acta 1984, 67, 856. (e) Jones, P. S.; Ley, S. V.; Simpkins, N. S.; Whittle, A. J. Tetrahedron 1986, 42, 6519. (f) Agami, G.; Platzer, N.; Puchot, C.; Sevestre, H. Tetrahedron 1987, 43, 1091 and references therein. (g) Kawamata, T.; Harimaya, K.; Inayama, S. Bull. Chem. Soc. Jp. 1988, 61, 3770. (h) Tori, M.; Furuta, H.; Asakawa, Y. J. Chem. Soc., Perkin Trans. 1 1991, 1919. (i) Gwaltney, S. L.; Sakata, S. T.; Shea, K. J. Tetrahedron Lett. 1995, 36, 7177. (j) La Clair, J. J.; Lansbury, P. T.; Zhi, B. X.; Hoogsteen, K. J. Org. Chem. 1995, 60, 4822.
26. For examples of structurally similar aldehyde/ketone-based intramolecular aldol reactions, see: (a) Danishefsky, S.; Zamboni, R.; Kahn, M.; Etheredge, S. J. J. Am. Chem. Soc. 1981, 103, 3460. (b) Bal, S. A.; Marfat, A.; Helquist, P. J. Org. Chem. 1982, 47, 5045. (c) Heathcock, C. H.; Kleinman, E. F.; Binkley, E. S. J. Am. Chem. Soc. 1982, 104, 1054. (d) Duthaler, R. O.; Maienfisch, P. Helv. Chim. Acta 1984, 67, 856. (e) Jones, P. S.; Ley, S. V.; Simpkins, N. S.; Whittle, A. J. Tetrahedron 1986, 42, 6519. (f) Agami, G.; Platzer, N.; Puchot, C.; Sevestre, H. Tetrahedron 1987, 43, 1091 and references therein. (g) Kawamata, T.; Harimaya, K.; Inayama, S. Bull. Chem. Soc. Jp. 1988, 61, 3770. (h) Tori, M.; Furuta, H.; Asakawa, Y. J. Chem. Soc., Perkin Trans. 1 1991, 1919. (i) Gwaltney, S. L.; Sakata, S. T.; Shea, K. J. Tetrahedron Lett. 1995, 36, 7177. (j) La Clair, J. J.; Lansbury, P. T.; Zhi, B. X.; Hoogsteen, K. J. Org. Chem. 1995, 60, 4822.
27. For examples of structurally similar aldehyde/ketone-based intramolecular aldol reactions, see: (a) Danishefsky, S.; Zamboni, R.; Kahn, M.; Etheredge, S. J. J. Am. Chem. Soc. 1981, 103, 3460. (b) Bal, S. A.; Marfat, A.; Helquist, P. J. Org. Chem. 1982, 47, 5045. (c) Heathcock, C. H.; Kleinman, E. F.; Binkley, E. S. J. Am. Chem. Soc. 1982, 104, 1054. (d) Duthaler, R. O.; Maienfisch, P. Helv. Chim. Acta 1984, 67, 856. (e) Jones, P. S.; Ley, S. V.; Simpkins, N. S.; Whittle, A. J. Tetrahedron 1986, 42, 6519. (f) Agami, G.; Platzer, N.; Puchot, C.; Sevestre, H. Tetrahedron 1987, 43, 1091 and references therein. (g) Kawamata, T.; Harimaya, K.; Inayama, S. Bull. Chem. Soc. Jp. 1988, 61, 3770. (h) Tori, M.; Furuta, H.; Asakawa, Y. J. Chem. Soc., Perkin Trans. 1 1991, 1919. (i) Gwaltney, S. L.; Sakata, S. T.; Shea, K. J. Tetrahedron Lett. 1995, 36, 7177. (j) La Clair, J. J.; Lansbury, P. T.; Zhi, B. X.; Hoogsteen, K. J. Org. Chem. 1995, 60, 4822.
28. For examples of structurally similar aldehyde/ketone-based intramolecular aldol reactions, see: (a) Danishefsky, S.; Zamboni, R.; Kahn, M.; Etheredge, S. J. J. Am. Chem. Soc. 1981, 103, 3460. (b) Bal, S. A.; Marfat, A.; Helquist, P. J. Org. Chem. 1982, 47, 5045. (c) Heathcock, C. H.; Kleinman, E. F.; Binkley, E. S. J. Am. Chem. Soc. 1982, 104, 1054. (d) Duthaler, R. O.; Maienfisch, P. Helv. Chim. Acta 1984, 67, 856. (e) Jones, P. S.; Ley, S. V.; Simpkins, N. S.; Whittle, A. J. Tetrahedron 1986, 42, 6519. (f) Agami, G.; Platzer, N.; Puchot, C.; Sevestre, H. Tetrahedron 1987, 43, 1091 and references therein. (g) Kawamata, T.; Harimaya, K.; Inayama, S. Bull. Chem. Soc. Jp. 1988, 61, 3770. (h) Tori, M.; Furuta, H.; Asakawa, Y. J. Chem. Soc., Perkin Trans. 1 1991, 1919. (i) Gwaltney, S. L.; Sakata, S. T.; Shea, K. J. Tetrahedron Lett. 1995, 36, 7177. (j) La Clair, J. J.; Lansbury, P. T.; Zhi, B. X.; Hoogsteen, K. J. Org. Chem. 1995, 60, 4822.
29. Garst, M. E.; Bonfiglio, J. N.; Grudoski, D. A.; Marks, J. J. Org. Chem. 1980, 45, 2307. For a solution to the problems associated with control of C(2) vs. C(4) regiochemistry in intermolecular aldol reactions of pyrrolidin-3-ones, see Thompson, S. H. J.; Subramanian, R. S.; Roberts, J. K.; Hadley, M. S.; Gallagher, T. J. Chem. Soc., Chem. Commun. 1994, 933 and references therein.
30. Garst, M. E.; Bonfiglio, J. N.; Grudoski, D. A.; Marks, J. J. Org. Chem. 1980, 45, 2307. For a solution to the problems associated with control of C(2) vs. C(4) regiochemistry in intermolecular aldol reactions of pyrrolidin-3-ones, see Thompson, S. H. J.; Subramanian, R. S.; Roberts, J. K.; Hadley, M. S.; Gallagher, T. J. Chem. Soc., Chem. Commun. 1994, 933 and references therein.
31. Viscontini, M.; Bühler, H. Helv. Chim. Acta 1967, 50, 1289.
32. Ketoaldehydes (1a-e) were all obtained using the amide coupling procedure shown in Scheme 1. Ketoaldehyde (1f) was prepared via acylation of (3) using allyl isocyanate. Benzylation (BnBr, NaH) of the initial adduct (1g), prior to ketal hydrolysis and oxidative cleavage, provided the N-benzyl variant. Ketoaldehyde (1h) was prepared via acylation of (3) with allyl chloroformate. All new compounds gave satisfactory spectroscopic data and were characterised by elemental analysis and/or high resolution mass measurement.
33. 3 solution at reflux (1-4 hr). The reaction mixture was washed with 2M HCl prior to being adsorbed onto silica gel (Merck 60H). In the case of (1b) → (2b), use of pyrrolidine in a catalytic quantity (10 mol%) is viable, but very slow reaction times make this unattractive at present.
34. Nielsen, A. T.; Houlihan, W. J. Org. React. 1968, 16, 1. For an example of an α-amino ketone undergoing an intermolecular amine-mediated aldol condensation, see Clemo, G. R.; Hoggarth., E. J. Chem. Soc. 1939, 1241. For a recent review of the intramolecular Mannich reaction see Overman, L. E.; Ricca, D. J. in Comprehensive Organic Synthesis; Trost, B. M.; Fleming, I. Eds.; Pergamon: Oxford, 1991, vol. 2, p. 1007.
35. Nielsen, A. T.; Houlihan, W. J. Org. React. 1968, 16, 1. For an example of an α-amino ketone undergoing an intermolecular amine-mediated aldol condensation, see Clemo, G. R.; Hoggarth., E. J. Chem. Soc. 1939, 1241. For a recent review of the intramolecular Mannich reaction see Overman, L. E.; Ricca, D. J. in Comprehensive Organic Synthesis; Trost, B. M.; Fleming, I. Eds.; Pergamon: Oxford, 1991, vol. 2, p. 1007.
36. Nielsen, A. T.; Houlihan, W. J. Org. React. 1968, 16, 1. For an example of an α-amino ketone undergoing an intermolecular amine-mediated aldol condensation, see Clemo, G. R.; Hoggarth., E. J. Chem. Soc. 1939, 1241. For a recent review of the intramolecular Mannich reaction see Overman, L. E.; Ricca, D. J. in Comprehensive Organic Synthesis; Trost, B. M.; Fleming, I. Eds.; Pergamon: Oxford, 1991, vol. 2, p. 1007.