γ-Lactam synthesis via C-H insertion: Elaboration of N-benzyl protecting groups for high regioselectivity toward the total synthesis of rolipram

Organic Letters

Volumn 5, Issue 13, 2003, Pages 2259-2262

  Yoon, Cheol Hwan ^a   Nagle, Advait ^a   Chen, Chiliu ^a   Gandhi, Drashti ^a   Jung, Kyung Woon ^a  

^a UNIVERSITY OF SOUTH FLORIDA   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ANTIDEPRESSANT AGENT; BENZYL DERIVATIVE; CARBON; GAMMA LACTAM DERIVATIVE; HYDROGEN; ROLIPRAM;

ADDITION REACTION; ARTICLE; DRUG SYNTHESIS; MOLECULAR INTERACTION; PROTON NUCLEAR MAGNETIC RESONANCE; STEREOCHEMISTRY;

ACETAMIDES; ANTIDEPRESSIVE AGENTS; LACTAMS; ROLIPRAM; SOLVENTS; STEREOISOMERISM; TOLUENE;

EID: 0141629752     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol0345834     Document Type: Article

References (38)

1. For the synthesis of γ-lactams by intramolecular C-H insertion reactions, see: (a) Doyle, M. P.; McKervey, M. A.; Ye, T. In Modern Catalytic Methods for Organic Synthesis with Diazo Compounds; Wiley-Interscience: New York, 1998, and references therein. (b) Doyle, M. P.; Taunton, J.; Pho, H. Q. Tetrahedron Lett. 1989, 30, 5397. (c) Doyle, M. P.; Pieters, R. J.; Taunton, J. ; Pho, H. Q. J. Org. Chem. 1991, 56, 820. (d) Wee, A. G. H.; Liu, B.; Zhang, L. J. Org. Chem. 1992, 57, 4404. (e) Padwa, A. P.; Austin, D. J.; Price, A. T.; Semones, M. A.; Doyle, M. P.; Protopopova, M. N.; Winchester, W. R.; Tran, A. J. Am. Chem. Soc. 1993, 115, 8669. (f) Zaragoza, F.; Zahn, G. J. Prakt. Chem. 1995, 292. (g) Wee, A. G. H.; Slobodian, J. J. Org. Chem. 1996, 61, 2897. (h) Doyle, M. P.; Kalinin, A. V. Tetrahedron Lett. 1996, 37, 1371. (i) Hashimoto, S.-I.; Anada, M. Tetrahedron Lett. 1998, 39, 79. (j) Wee, A. G. H.; Liu, B.; McLeod, D. D. J. Org. Chem. 1998, 63, 4218. (k) Moody, C. J.; Miah, S.; Slawin, A. M. Z.; Mansfield, D. J.; Richards, I. C. Tetrahedron 1998, 54, 9689. (l) Wee, A. G. H.; Duncan, S. C. Tetrahedron Lett. 2002, 43, 6173.
2. For the synthesis of γ-lactams by intramolecular C-H insertion reactions, see: (a) Doyle, M. P.; McKervey, M. A.; Ye, T. In Modern Catalytic Methods for Organic Synthesis with Diazo Compounds; Wiley-Interscience: New York, 1998, and references therein. (b) Doyle, M. P.; Taunton, J.; Pho, H. Q. Tetrahedron Lett. 1989, 30, 5397. (c) Doyle, M. P.; Pieters, R. J.; Taunton, J. ; Pho, H. Q. J. Org. Chem. 1991, 56, 820. (d) Wee, A. G. H.; Liu, B.; Zhang, L. J. Org. Chem. 1992, 57, 4404. (e) Padwa, A. P.; Austin, D. J.; Price, A. T.; Semones, M. A.; Doyle, M. P.; Protopopova, M. N.; Winchester, W. R.; Tran, A. J. Am. Chem. Soc. 1993, 115, 8669. (f) Zaragoza, F.; Zahn, G. J. Prakt. Chem. 1995, 292. (g) Wee, A. G. H.; Slobodian, J. J. Org. Chem. 1996, 61, 2897. (h) Doyle, M. P.; Kalinin, A. V. Tetrahedron Lett. 1996, 37, 1371. (i) Hashimoto, S.-I.; Anada, M. Tetrahedron Lett. 1998, 39, 79. (j) Wee, A. G. H.; Liu, B.; McLeod, D. D. J. Org. Chem. 1998, 63, 4218. (k) Moody, C. J.; Miah, S.; Slawin, A. M. Z.; Mansfield, D. J.; Richards, I. C. Tetrahedron 1998, 54, 9689. (l) Wee, A. G. H.; Duncan, S. C. Tetrahedron Lett. 2002, 43, 6173.
3. For the synthesis of γ-lactams by intramolecular C-H insertion reactions, see: (a) Doyle, M. P.; McKervey, M. A.; Ye, T. In Modern Catalytic Methods for Organic Synthesis with Diazo Compounds; Wiley-Interscience: New York, 1998, and references therein. (b) Doyle, M. P.; Taunton, J.; Pho, H. Q. Tetrahedron Lett. 1989, 30, 5397. (c) Doyle, M. P.; Pieters, R. J.; Taunton, J. ; Pho, H. Q. J. Org. Chem. 1991, 56, 820. (d) Wee, A. G. H.; Liu, B.; Zhang, L. J. Org. Chem. 1992, 57, 4404. (e) Padwa, A. P.; Austin, D. J.; Price, A. T.; Semones, M. A.; Doyle, M. P.; Protopopova, M. N.; Winchester, W. R.; Tran, A. J. Am. Chem. Soc. 1993, 115, 8669. (f) Zaragoza, F.; Zahn, G. J. Prakt. Chem. 1995, 292. (g) Wee, A. G. H.; Slobodian, J. J. Org. Chem. 1996, 61, 2897. (h) Doyle, M. P.; Kalinin, A. V. Tetrahedron Lett. 1996, 37, 1371. (i) Hashimoto, S.-I.; Anada, M. Tetrahedron Lett. 1998, 39, 79. (j) Wee, A. G. H.; Liu, B.; McLeod, D. D. J. Org. Chem. 1998, 63, 4218. (k) Moody, C. J.; Miah, S.; Slawin, A. M. Z.; Mansfield, D. J.; Richards, I. C. Tetrahedron 1998, 54, 9689. (l) Wee, A. G. H.; Duncan, S. C. Tetrahedron Lett. 2002, 43, 6173.
4. For the synthesis of γ-lactams by intramolecular C-H insertion reactions, see: (a) Doyle, M. P.; McKervey, M. A.; Ye, T. In Modern Catalytic Methods for Organic Synthesis with Diazo Compounds; Wiley-Interscience: New York, 1998, and references therein. (b) Doyle, M. P.; Taunton, J.; Pho, H. Q. Tetrahedron Lett. 1989, 30, 5397. (c) Doyle, M. P.; Pieters, R. J.; Taunton, J. ; Pho, H. Q. J. Org. Chem. 1991, 56, 820. (d) Wee, A. G. H.; Liu, B.; Zhang, L. J. Org. Chem. 1992, 57, 4404. (e) Padwa, A. P.; Austin, D. J.; Price, A. T.; Semones, M. A.; Doyle, M. P.; Protopopova, M. N.; Winchester, W. R.; Tran, A. J. Am. Chem. Soc. 1993, 115, 8669. (f) Zaragoza, F.; Zahn, G. J. Prakt. Chem. 1995, 292. (g) Wee, A. G. H.; Slobodian, J. J. Org. Chem. 1996, 61, 2897. (h) Doyle, M. P.; Kalinin, A. V. Tetrahedron Lett. 1996, 37, 1371. (i) Hashimoto, S.-I.; Anada, M. Tetrahedron Lett. 1998, 39, 79. (j) Wee, A. G. H.; Liu, B.; McLeod, D. D. J. Org. Chem. 1998, 63, 4218. (k) Moody, C. J.; Miah, S.; Slawin, A. M. Z.; Mansfield, D. J.; Richards, I. C. Tetrahedron 1998, 54, 9689. (l) Wee, A. G. H.; Duncan, S. C. Tetrahedron Lett. 2002, 43, 6173.
5. For the synthesis of γ-lactams by intramolecular C-H insertion reactions, see: (a) Doyle, M. P.; McKervey, M. A.; Ye, T. In Modern Catalytic Methods for Organic Synthesis with Diazo Compounds; Wiley-Interscience: New York, 1998, and references therein. (b) Doyle, M. P.; Taunton, J.; Pho, H. Q. Tetrahedron Lett. 1989, 30, 5397. (c) Doyle, M. P.; Pieters, R. J.; Taunton, J. ; Pho, H. Q. J. Org. Chem. 1991, 56, 820. (d) Wee, A. G. H.; Liu, B.; Zhang, L. J. Org. Chem. 1992, 57, 4404. (e) Padwa, A. P.; Austin, D. J.; Price, A. T.; Semones, M. A.; Doyle, M. P.; Protopopova, M. N.; Winchester, W. R.; Tran, A. J. Am. Chem. Soc. 1993, 115, 8669. (f) Zaragoza, F.; Zahn, G. J. Prakt. Chem. 1995, 292. (g) Wee, A. G. H.; Slobodian, J. J. Org. Chem. 1996, 61, 2897. (h) Doyle, M. P.; Kalinin, A. V. Tetrahedron Lett. 1996, 37, 1371. (i) Hashimoto, S.-I.; Anada, M. Tetrahedron Lett. 1998, 39, 79. (j) Wee, A. G. H.; Liu, B.; McLeod, D. D. J. Org. Chem. 1998, 63, 4218. (k) Moody, C. J.; Miah, S.; Slawin, A. M. Z.; Mansfield, D. J.; Richards, I. C. Tetrahedron 1998, 54, 9689. (l) Wee, A. G. H.; Duncan, S. C. Tetrahedron Lett. 2002, 43, 6173.
6. For the synthesis of γ-lactams by intramolecular C-H insertion reactions, see: (a) Doyle, M. P.; McKervey, M. A.; Ye, T. In Modern Catalytic Methods for Organic Synthesis with Diazo Compounds; Wiley-Interscience: New York, 1998, and references therein. (b) Doyle, M. P.; Taunton, J.; Pho, H. Q. Tetrahedron Lett. 1989, 30, 5397. (c) Doyle, M. P.; Pieters, R. J.; Taunton, J. ; Pho, H. Q. J. Org. Chem. 1991, 56, 820. (d) Wee, A. G. H.; Liu, B.; Zhang, L. J. Org. Chem. 1992, 57, 4404. (e) Padwa, A. P.; Austin, D. J.; Price, A. T.; Semones, M. A.; Doyle, M. P.; Protopopova, M. N.; Winchester, W. R.; Tran, A. J. Am. Chem. Soc. 1993, 115, 8669. (f) Zaragoza, F.; Zahn, G. J. Prakt. Chem. 1995, 292. (g) Wee, A. G. H.; Slobodian, J. J. Org. Chem. 1996, 61, 2897. (h) Doyle, M. P.; Kalinin, A. V. Tetrahedron Lett. 1996, 37, 1371. (i) Hashimoto, S.-I.; Anada, M. Tetrahedron Lett. 1998, 39, 79. (j) Wee, A. G. H.; Liu, B.; McLeod, D. D. J. Org. Chem. 1998, 63, 4218. (k) Moody, C. J.; Miah, S.; Slawin, A. M. Z.; Mansfield, D. J.; Richards, I. C. Tetrahedron 1998, 54, 9689. (l) Wee, A. G. H.; Duncan, S. C. Tetrahedron Lett. 2002, 43, 6173.
7. For the synthesis of γ-lactams by intramolecular C-H insertion reactions, see: (a) Doyle, M. P.; McKervey, M. A.; Ye, T. In Modern Catalytic Methods for Organic Synthesis with Diazo Compounds; Wiley-Interscience: New York, 1998, and references therein. (b) Doyle, M. P.; Taunton, J.; Pho, H. Q. Tetrahedron Lett. 1989, 30, 5397. (c) Doyle, M. P.; Pieters, R. J.; Taunton, J. ; Pho, H. Q. J. Org. Chem. 1991, 56, 820. (d) Wee, A. G. H.; Liu, B.; Zhang, L. J. Org. Chem. 1992, 57, 4404. (e) Padwa, A. P.; Austin, D. J.; Price, A. T.; Semones, M. A.; Doyle, M. P.; Protopopova, M. N.; Winchester, W. R.; Tran, A. J. Am. Chem. Soc. 1993, 115, 8669. (f) Zaragoza, F.; Zahn, G. J. Prakt. Chem. 1995, 292. (g) Wee, A. G. H.; Slobodian, J. J. Org. Chem. 1996, 61, 2897. (h) Doyle, M. P.; Kalinin, A. V. Tetrahedron Lett. 1996, 37, 1371. (i) Hashimoto, S.-I.; Anada, M. Tetrahedron Lett. 1998, 39, 79. (j) Wee, A. G. H.; Liu, B.; McLeod, D. D. J. Org. Chem. 1998, 63, 4218. (k) Moody, C. J.; Miah, S.; Slawin, A. M. Z.; Mansfield, D. J.; Richards, I. C. Tetrahedron 1998, 54, 9689. (l) Wee, A. G. H.; Duncan, S. C. Tetrahedron Lett. 2002, 43, 6173.
8. For the synthesis of γ-lactams by intramolecular C-H insertion reactions, see: (a) Doyle, M. P.; McKervey, M. A.; Ye, T. In Modern Catalytic Methods for Organic Synthesis with Diazo Compounds; Wiley-Interscience: New York, 1998, and references therein. (b) Doyle, M. P.; Taunton, J.; Pho, H. Q. Tetrahedron Lett. 1989, 30, 5397. (c) Doyle, M. P.; Pieters, R. J.; Taunton, J. ; Pho, H. Q. J. Org. Chem. 1991, 56, 820. (d) Wee, A. G. H.; Liu, B.; Zhang, L. J. Org. Chem. 1992, 57, 4404. (e) Padwa, A. P.; Austin, D. J.; Price, A. T.; Semones, M. A.; Doyle, M. P.; Protopopova, M. N.; Winchester, W. R.; Tran, A. J. Am. Chem. Soc. 1993, 115, 8669. (f) Zaragoza, F.; Zahn, G. J. Prakt. Chem. 1995, 292. (g) Wee, A. G. H.; Slobodian, J. J. Org. Chem. 1996, 61, 2897. (h) Doyle, M. P.; Kalinin, A. V. Tetrahedron Lett. 1996, 37, 1371. (i) Hashimoto, S.-I.; Anada, M. Tetrahedron Lett. 1998, 39, 79. (j) Wee, A. G. H.; Liu, B.; McLeod, D. D. J. Org. Chem. 1998, 63, 4218. (k) Moody, C. J.; Miah, S.; Slawin, A. M. Z.; Mansfield, D. J.; Richards, I. C. Tetrahedron 1998, 54, 9689. (l) Wee, A. G. H.; Duncan, S. C. Tetrahedron Lett. 2002, 43, 6173.
9. For the synthesis of γ-lactams by intramolecular C-H insertion reactions, see: (a) Doyle, M. P.; McKervey, M. A.; Ye, T. In Modern Catalytic Methods for Organic Synthesis with Diazo Compounds; Wiley-Interscience: New York, 1998, and references therein. (b) Doyle, M. P.; Taunton, J.; Pho, H. Q. Tetrahedron Lett. 1989, 30, 5397. (c) Doyle, M. P.; Pieters, R. J.; Taunton, J. ; Pho, H. Q. J. Org. Chem. 1991, 56, 820. (d) Wee, A. G. H.; Liu, B.; Zhang, L. J. Org. Chem. 1992, 57, 4404. (e) Padwa, A. P.; Austin, D. J.; Price, A. T.; Semones, M. A.; Doyle, M. P.; Protopopova, M. N.; Winchester, W. R.; Tran, A. J. Am. Chem. Soc. 1993, 115, 8669. (f) Zaragoza, F.; Zahn, G. J. Prakt. Chem. 1995, 292. (g) Wee, A. G. H.; Slobodian, J. J. Org. Chem. 1996, 61, 2897. (h) Doyle, M. P.; Kalinin, A. V. Tetrahedron Lett. 1996, 37, 1371. (i) Hashimoto, S.-I.; Anada, M. Tetrahedron Lett. 1998, 39, 79. (j) Wee, A. G. H.; Liu, B.; McLeod, D. D. J. Org. Chem. 1998, 63, 4218. (k) Moody, C. J.; Miah, S.; Slawin, A. M. Z.; Mansfield, D. J.; Richards, I. C. Tetrahedron 1998, 54, 9689. (l) Wee, A. G. H.; Duncan, S. C. Tetrahedron Lett. 2002, 43, 6173.
10. For the synthesis of γ-lactams by intramolecular C-H insertion reactions, see: (a) Doyle, M. P.; McKervey, M. A.; Ye, T. In Modern Catalytic Methods for Organic Synthesis with Diazo Compounds; Wiley-Interscience: New York, 1998, and references therein. (b) Doyle, M. P.; Taunton, J.; Pho, H. Q. Tetrahedron Lett. 1989, 30, 5397. (c) Doyle, M. P.; Pieters, R. J.; Taunton, J. ; Pho, H. Q. J. Org. Chem. 1991, 56, 820. (d) Wee, A. G. H.; Liu, B.; Zhang, L. J. Org. Chem. 1992, 57, 4404. (e) Padwa, A. P.; Austin, D. J.; Price, A. T.; Semones, M. A.; Doyle, M. P.; Protopopova, M. N.; Winchester, W. R.; Tran, A. J. Am. Chem. Soc. 1993, 115, 8669. (f) Zaragoza, F.; Zahn, G. J. Prakt. Chem. 1995, 292. (g) Wee, A. G. H.; Slobodian, J. J. Org. Chem. 1996, 61, 2897. (h) Doyle, M. P.; Kalinin, A. V. Tetrahedron Lett. 1996, 37, 1371. (i) Hashimoto, S.-I.; Anada, M. Tetrahedron Lett. 1998, 39, 79. (j) Wee, A. G. H.; Liu, B.; McLeod, D. D. J. Org. Chem. 1998, 63, 4218. (k) Moody, C. J.; Miah, S.; Slawin, A. M. Z.; Mansfield, D. J.; Richards, I. C. Tetrahedron 1998, 54, 9689. (l) Wee, A. G. H.; Duncan, S. C. Tetrahedron Lett. 2002, 43, 6173.
11. For the synthesis of γ-lactams by intramolecular C-H insertion reactions, see: (a) Doyle, M. P.; McKervey, M. A.; Ye, T. In Modern Catalytic Methods for Organic Synthesis with Diazo Compounds; Wiley-Interscience: New York, 1998, and references therein. (b) Doyle, M. P.; Taunton, J.; Pho, H. Q. Tetrahedron Lett. 1989, 30, 5397. (c) Doyle, M. P.; Pieters, R. J.; Taunton, J. ; Pho, H. Q. J. Org. Chem. 1991, 56, 820. (d) Wee, A. G. H.; Liu, B.; Zhang, L. J. Org. Chem. 1992, 57, 4404. (e) Padwa, A. P.; Austin, D. J.; Price, A. T.; Semones, M. A.; Doyle, M. P.; Protopopova, M. N.; Winchester, W. R.; Tran, A. J. Am. Chem. Soc. 1993, 115, 8669. (f) Zaragoza, F.; Zahn, G. J. Prakt. Chem. 1995, 292. (g) Wee, A. G. H.; Slobodian, J. J. Org. Chem. 1996, 61, 2897. (h) Doyle, M. P.; Kalinin, A. V. Tetrahedron Lett. 1996, 37, 1371. (i) Hashimoto, S.-I.; Anada, M. Tetrahedron Lett. 1998, 39, 79. (j) Wee, A. G. H.; Liu, B.; McLeod, D. D. J. Org. Chem. 1998, 63, 4218. (k) Moody, C. J.; Miah, S.; Slawin, A. M. Z.; Mansfield, D. J.; Richards, I. C. Tetrahedron 1998, 54, 9689. (l) Wee, A. G. H.; Duncan, S. C. Tetrahedron Lett. 2002, 43, 6173.
12. For the synthesis of γ-lactams by intramolecular C-H insertion reactions, see: (a) Doyle, M. P.; McKervey, M. A.; Ye, T. In Modern Catalytic Methods for Organic Synthesis with Diazo Compounds; Wiley-Interscience: New York, 1998, and references therein. (b) Doyle, M. P.; Taunton, J.; Pho, H. Q. Tetrahedron Lett. 1989, 30, 5397. (c) Doyle, M. P.; Pieters, R. J.; Taunton, J. ; Pho, H. Q. J. Org. Chem. 1991, 56, 820. (d) Wee, A. G. H.; Liu, B.; Zhang, L. J. Org. Chem. 1992, 57, 4404. (e) Padwa, A. P.; Austin, D. J.; Price, A. T.; Semones, M. A.; Doyle, M. P.; Protopopova, M. N.; Winchester, W. R.; Tran, A. J. Am. Chem. Soc. 1993, 115, 8669. (f) Zaragoza, F.; Zahn, G. J. Prakt. Chem. 1995, 292. (g) Wee, A. G. H.; Slobodian, J. J. Org. Chem. 1996, 61, 2897. (h) Doyle, M. P.; Kalinin, A. V. Tetrahedron Lett. 1996, 37, 1371. (i) Hashimoto, S.-I.; Anada, M. Tetrahedron Lett. 1998, 39, 79. (j) Wee, A. G. H.; Liu, B.; McLeod, D. D. J. Org. Chem. 1998, 63, 4218. (k) Moody, C. J.; Miah, S.; Slawin, A. M. Z.; Mansfield, D. J.; Richards, I. C. Tetrahedron 1998, 54, 9689. (l) Wee, A. G. H.; Duncan, S. C. Tetrahedron Lett. 2002, 43, 6173.
13. Padwa, A.; Austin, D. J. Angew. Chem., Int. Ed. Engl. 1994, 33, 1797.
14. Yoon, C. H.; Zaworotko, M. J.; Moulton, B.; Jung, K. W. Org. Lett. 2001, 3, 3539.
15. For the synthesis of (+)-rolipram, see: (a) Barluenga, J.; Fernández-Rodríguez, M. A.; Aguilar, E.; Ferná ndez-Marí, F.; Salinas, A.; Olano, B. Chem. Eur. J. 2001, 7, 4323. (b) Demniz, J.; LaVecchia, L.; Bacher, E.; Keller, T. H.; Schurch, F.; Weber, H. P. ; Pombo-Villar, E. Molecules 1998, 3, 107. (c) Mulzer, J. J. Prakt. Chem. 1994, 336, 287 and references therein.
16. For the synthesis of (+)-rolipram, see: (a) Barluenga, J.; Fernández-Rodríguez, M. A.; Aguilar, E.; Ferná ndez-Marí, F.; Salinas, A.; Olano, B. Chem. Eur. J. 2001, 7, 4323. (b) Demniz, J.; LaVecchia, L.; Bacher, E.; Keller, T. H.; Schurch, F.; Weber, H. P. ; Pombo-Villar, E. Molecules 1998, 3, 107. (c) Mulzer, J. J. Prakt. Chem. 1994, 336, 287 and references therein.
17. For the synthesis of (+)-rolipram, see: (a) Barluenga, J.; Fernández-Rodríguez, M. A.; Aguilar, E.; Ferná ndez-Marí, F.; Salinas, A.; Olano, B. Chem. Eur. J. 2001, 7, 4323. (b) Demniz, J.; LaVecchia, L.; Bacher, E.; Keller, T. H.; Schurch, F.; Weber, H. P. ; Pombo-Villar, E. Molecules 1998, 3, 107. (c) Mulzer, J. J. Prakt. Chem. 1994, 336, 287 and references therein.
18. For the synthesis of (-)-rolipram, see: (a) Itoh, K.; Kanemasa, S. J. Am. Chem. Soc. 2002, 124, 13394. (b) Barnes, D. M.; Ji, J.; Fickes, M. G.; Fitzgerald, M. A.; King, S. A.; Morton, H. E.; Plagge, F. A.; Preskill, M.; Wagaw, S. H.; Wittenberger, S. J.; Zhang, J. J. Am. Chem. Soc. 2002, 124, 13097. (c) For the synthesis of (-)-rolipram via C-H insertion reaction, see: Anada, M.; Mita, O.; Watanabe, H.; Kitagaki, S.; Hashimoto, S. Synlett 1999, 1775.
19. For the synthesis of (-)-rolipram, see: (a) Itoh, K.; Kanemasa, S. J. Am. Chem. Soc. 2002, 124, 13394. (b) Barnes, D. M.; Ji, J.; Fickes, M. G.; Fitzgerald, M. A.; King, S. A.; Morton, H. E.; Plagge, F. A.; Preskill, M.; Wagaw, S. H.; Wittenberger, S. J.; Zhang, J. J. Am. Chem. Soc. 2002, 124, 13097. (c) For the synthesis of (-)-rolipram via C-H insertion reaction, see: Anada, M.; Mita, O.; Watanabe, H.; Kitagaki, S.; Hashimoto, S. Synlett 1999, 1775.
20. For the synthesis of (-)-rolipram, see: (a) Itoh, K.; Kanemasa, S. J. Am. Chem. Soc. 2002, 124, 13394. (b) Barnes, D. M.; Ji, J.; Fickes, M. G.; Fitzgerald, M. A.; King, S. A.; Morton, H. E.; Plagge, F. A.; Preskill, M.; Wagaw, S. H.; Wittenberger, S. J.; Zhang, J. J. Am. Chem. Soc. 2002, 124, 13097. (c) For the synthesis of (-)-rolipram via C-H insertion reaction, see: Anada, M.; Mita, O.; Watanabe, H.; Kitagaki, S.; Hashimoto, S. Synlett 1999, 1775.
21. Greene, T. W.; Wuts, P. G. In Protective Groups in Organic Synthesis; Wiley-Interscience: New York, 1999.
22. 2, cooled to room temperature, and concentrated. The residue was chromatographed to give γ- and β-lactams.
23. 3,4 (12) = 3.5 Hz.
24. (a) Taber, D. F.; Ruckle, R. E., Jr. J. Am. Chem. Soc. 1986, 108, 7686.
25. (b) Doyle, M. P.; Westrum, L. J.; Wolthuis, W. N. E.; See, M. M.; Boone, W. P.; Bagheri, V.; Pearson, M. M. J. Am. Chem. Soc. 1993, 115, 958.
26. 1H NMR analysis after the deprotection of the 4-methoxybenzyl group. See Supporting Information.
27. For the aromatic cycloaddition of diazoamides, see: (a) Doyle, M. P.; Shanklin, M. S.; Pho, H. Q. Tetrahedron Lett. 1988, 29, 2639. (b) Doyle, M. P.; Shanklin, M. S.; Oon, S. M.; Pho, H. Q.; van der Heide, F. R.; Veal, W. R. J. Org. Chem. 1988, 53, 3386. (c) Padwa, A.; Austin, D. J.; Hornbuckle, S. F.; Semones, M. A.; Doyle, M. P.; Protopopova, M. N. J. Am. Chem. Soc. 1992, 114, 1874. (d) Miah, S.; Slawin, A. M. Z.; Moody, C. J.; Sheehan, S. M.; Marino, J. P., Jr.; Semones, M. A.; Padwa, A. Tetrahedron 1996, 52, 2489. (e) Merlic, C. A.; Zechman, A. L.; Miller, M. M. J. Am. Chem. Soc. 2001, 123, 11101.
28. For the aromatic cycloaddition of diazoamides, see: (a) Doyle, M. P.; Shanklin, M. S.; Pho, H. Q. Tetrahedron Lett. 1988, 29, 2639. (b) Doyle, M. P.; Shanklin, M. S.; Oon, S. M.; Pho, H. Q.; van der Heide, F. R.; Veal, W. R. J. Org. Chem. 1988, 53, 3386. (c) Padwa, A.; Austin, D. J.; Hornbuckle, S. F.; Semones, M. A.; Doyle, M. P.; Protopopova, M. N. J. Am. Chem. Soc. 1992, 114, 1874. (d) Miah, S.; Slawin, A. M. Z.; Moody, C. J.; Sheehan, S. M.; Marino, J. P., Jr.; Semones, M. A.; Padwa, A. Tetrahedron 1996, 52, 2489. (e) Merlic, C. A.; Zechman, A. L.; Miller, M. M. J. Am. Chem. Soc. 2001, 123, 11101.
29. For the aromatic cycloaddition of diazoamides, see: (a) Doyle, M. P.; Shanklin, M. S.; Pho, H. Q. Tetrahedron Lett. 1988, 29, 2639. (b) Doyle, M. P.; Shanklin, M. S.; Oon, S. M.; Pho, H. Q.; van der Heide, F. R.; Veal, W. R. J. Org. Chem. 1988, 53, 3386. (c) Padwa, A.; Austin, D. J.; Hornbuckle, S. F.; Semones, M. A.; Doyle, M. P.; Protopopova, M. N. J. Am. Chem. Soc. 1992, 114, 1874. (d) Miah, S.; Slawin, A. M. Z.; Moody, C. J.; Sheehan, S. M.; Marino, J. P., Jr.; Semones, M. A.; Padwa, A. Tetrahedron 1996, 52, 2489. (e) Merlic, C. A.; Zechman, A. L.; Miller, M. M. J. Am. Chem. Soc. 2001, 123, 11101.
30. For the aromatic cycloaddition of diazoamides, see: (a) Doyle, M. P.; Shanklin, M. S.; Pho, H. Q. Tetrahedron Lett. 1988, 29, 2639. (b) Doyle, M. P.; Shanklin, M. S.; Oon, S. M.; Pho, H. Q.; van der Heide, F. R.; Veal, W. R. J. Org. Chem. 1988, 53, 3386. (c) Padwa, A.; Austin, D. J.; Hornbuckle, S. F.; Semones, M. A.; Doyle, M. P.; Protopopova, M. N. J. Am. Chem. Soc. 1992, 114, 1874. (d) Miah, S.; Slawin, A. M. Z.; Moody, C. J.; Sheehan, S. M.; Marino, J. P., Jr.; Semones, M. A.; Padwa, A. Tetrahedron 1996, 52, 2489. (e) Merlic, C. A.; Zechman, A. L.; Miller, M. M. J. Am. Chem. Soc. 2001, 123, 11101.
31. For the aromatic cycloaddition of diazoamides, see: (a) Doyle, M. P.; Shanklin, M. S.; Pho, H. Q. Tetrahedron Lett. 1988, 29, 2639. (b) Doyle, M. P.; Shanklin, M. S.; Oon, S. M.; Pho, H. Q.; van der Heide, F. R.; Veal, W. R. J. Org. Chem. 1988, 53, 3386. (c) Padwa, A.; Austin, D. J.; Hornbuckle, S. F.; Semones, M. A.; Doyle, M. P.; Protopopova, M. N. J. Am. Chem. Soc. 1992, 114, 1874. (d) Miah, S.; Slawin, A. M. Z.; Moody, C. J.; Sheehan, S. M.; Marino, J. P., Jr.; Semones, M. A.; Padwa, A. Tetrahedron 1996, 52, 2489. (e) Merlic, C. A.; Zechman, A. L.; Miller, M. M. J. Am. Chem. Soc. 2001, 123, 11101.
32. Davies, H. M. L.; Panaro, S. A. Tetrahedron 2000, 56, 4871.
33. (a) Doyle, M. P.; Dyatkin, A. B.; Autry, C. L. J. Chem. Soc., Perkin Trans. 1 1995, 34, 78.
34. (b) ref 1f.
35. Diazocompound 43 was derived from cumylamine (2,2,-dimethyl-benzylamine), which was very expensive ($91.15/5 mL, available from TCI). Despite the higher yield of cyclization of 26, the 2,4-dimethoxy benzyl protecting group was excluded due to the formation of β-lactam.
36. (a) Seika, M. Drugs Future 1998, 23, 108.
37. (b) Sommer, N.; Loeschmann, P. A.; Northoff, G. H.; Weller, M.; Steinbrecher, A.; Steinbach, J. P.; Richtenfiels, R.; Meyermann, R.; Reithmueller, A.; Fontana, A.; Dichgans, J.; Martin, R. Nat. Med. 1995, 1, 244.
38. (c) Baures, P. W.; Egglestone, D. S.; Erhard, K. F.; Cieslinski, L. B.; Trophy, T. J.; Christensen, S. B. J. Med. Chem. 1993, 36,