Selective Alkylation of Ketones with a Bulky Aluminum Reagent-the THF-TBSOTf System

Synlett

Volumn 1997, Issue 4, 1997, Pages 357-358

  Saito, Susumu ^a   Ito, Masahiro ^a   Maruoka, Keiji ^a,b   Yamamoto, Hisashi ^a  

^a NAGOYA UNIVERSITY   (Japan)

^b HOKKAIDO UNIVERSITY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 0001790833     PISSN: 09365214     EISSN: None     Source Type: Journal    
DOI: 10.1055/s-1997-792     Document Type: Article

References (27)

1. (a) Maruoka, K.; Imoto, H; Saito, S.; Yamamoto, H.; J. Am. Chem. Soc., 1994, 116, 4131.
2. (b) Maruoka, K.; Saito, S.; Yamamoto, H.; Synlett, 1994, 439.
3. (c) Maruoka, K.; Saito, S.; Yamamoto, H.; J. Am. Chem. Soc., 1995, 117, 1165
4. (a) Maruoka, K.; Araki, Y.; Yamamoto, H. J. Am. Chem. Soc. 1988, 110, 2650.
5. (b) Maruoka, K.; Itoh, T.; Sakurai, M.; Nonoshita, K.; Yamamoto, H. J. Am. Chem. Soc. 1988, 110, 3588.
6. (c) Maruoka, K.; Nagahara, S.; Yamamoto, H. ibid. 1990, 112, 6225.
7. (d) Maruoka, K.; Nagahara, S.; Yamamoto, H. Tetrahedron Lett. 1990, 31, 5475.
8. (e) Maruoka, K.; Saito, S.; Yamamoto, H. J. Am. Chem. Soc. 1992, 114, 1089.
9. This reaction was eventually found during our research on the conjugate addition of t-butyllithium (t-BuLi) to acetophenone in the presence of ATPH (in toluene-THF), followed by subsequent treatment with TBSOTf, as shown below. (Formula Presented)
10. (a) Stork, G.; Hudrlik, P. F. J. Am. Chem. Soc. 1968, 4462.
11. (b) Stork, G.; Hudrlik, P. F. Ibid. 1968, 4464.
12. Maruoka, K.; Shimada, I.; Imoto, H.; Yamamoto, H. Synlett 1994, 519.
13. 3) analysis by measuring the coupling constant (Hz) of C(2)H of 1. Trans-1: δ 2.38 (dt, 1H, J = 13.3, 4.9 Hz)
14. Selective 1,4-reduction of α-enones with ATPH: Saito, S.; Yamamoto, H. J. Org. Chem. 1996, 61, 2928.
15. 3) analysis and by comparing the chemical shifts (ppm) of the Megroups of trans- and cis-2 (trans-2: δ 1.02 (d, J = 6.2 Hz); cis-2: δ 0.97 (d, J = 6.6 Hz) with those of trans- and cis-3,5-dimethylcyclohexanone (trans: δ 0.99 (d, J = 6.8 Hz); cis: δ 1.02 (d, J = 6.0 Hz)).
16. 13C NMR, and elemental analysis. Preparation of ATPH: see reference 1a.
17. (10) Using MAD (1.1 equiv) in place of ATPH (1.1 equiv) in the same reaction sequence resulted in the immediate consumption of ketone 3, followed by subsequent production of a mixture of 5 and 10 (∼ 2.4: 1). Preparation of MAD: see reference 2b.
18. Alkylation at the more substituted α-site of unsymmetrical ketones using ATPH: Saito, S.; Ito, M.; Yamamoto, H., J. Am. Chem. Soc., 1997, 119, 611.
19. Regioselective alkylation at the more-substituted α-site of 4 under thermodynamic conditions has been reported, but the selectivity was much lower: House, H. O.; Gall, M.; Olmstead, H. D.; J. Org. Chem., 1971, 36, 2361. (b) House, H. O; Trost, B. M.; ibid. 1965, 30, 1341. See also reference 11, and other references cited therein.
20. Regioselective alkylation at the more-substituted α-site of 4 under thermodynamic conditions has been reported, but the selectivity was much lower: House, H. O.; Gall, M.; Olmstead, H. D.; J. Org. Chem., 1971, 36, 2361. (b) House, H. O; Trost, B. M.; ibid. 1965, 30, 1341. See also reference 11, and other references cited therein.
21. One-pot α,α'-dialkylation of ketones: Bates, R. B.; Taylor, S. R. J. Org. Chem. 1994, 59, 245.
22. Lohray, B. B.; Enders, D.; Synthesis, 1993, 1092.
23. Ring opening reaction of cyclic ethers: (a) Guindon, Y.; Theriene, M.; Girard, Y.; Yoakim, C.; J. Org. Chem., 1987, 52, 1680. (b) Kricheldorf, H. R.; Morber, G.; Regel, W. Synthesis 1981, 383. (c) Jung, M. E.; Hatfield, G. L.; Tetrahedron Lett. 1978, 4483.
24. Ring opening reaction of cyclic ethers: (a) Guindon, Y.; Theriene, M.; Girard, Y.; Yoakim, C.; J. Org. Chem., 1987, 52, 1680. (b) Kricheldorf, H. R.; Morber, G.; Regel, W. Synthesis 1981, 383. (c) Jung, M. E.; Hatfield, G. L.; Tetrahedron Lett. 1978, 4483.
25. Ring opening reaction of cyclic ethers: (a) Guindon, Y.; Theriene, M.; Girard, Y.; Yoakim, C.; J. Org. Chem., 1987, 52, 1680. (b) Kricheldorf, H. R.; Morber, G.; Regel, W. Synthesis 1981, 383. (c) Jung, M. E.; Hatfield, G. L.; Tetrahedron Lett. 1978, 4483.
26. (d) Andrews, G. C.; Crawford, T. C.; Contillo, Jr. L. G. ibid. 1981, 22, 3803.
27. (e) M. J. Eis, J. E. Wrobel, B. Ganem. J. Am. Chem. Soc., 1984, 106, 3693.