Enantioselective alkylation of lactams and lactones via lithium enolate formation using a chiral tetradentate lithium amide in the presence of lithium bromide

Tetrahedron Letters

Volumn 39, Issue 52, 1998, Pages 9723-9726

  Matsuo, Jun Ichi ^a   Kobayashi, Shu ^a   Koga, Kenji ^a,b  

^a UNIVERSITY OF TOKYO   (Japan)

^b NARA INSTITUTE OF SCIENCE AND TECHNOLOGY   (Japan)

Author keywords

Alkylation; Asymmetric reaction; Lactam; Lactone

Indexed keywords

ALKYLATING AGENT; AMIDE; BROMINE DERIVATIVE; LACTAM DERIVATIVE; LACTONE DERIVATIVE; LITHIUM DERIVATIVE; SOLVENT;

ALKYLATION; ARTICLE; CATALYSIS; CHEMICAL REACTION; CHIRALITY; ENANTIOMER; STEREOCHEMISTRY; STOICHIOMETRY; SYNTHESIS;

EID: 0032564531     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(98)02235-7     Document Type: Article

References (17)

1. (1) a) Evans, D. A. Asymmetric Synthesis; Morrison, J. D., Ed.; Academic Press: Orland, FL, 1984; pp 1-110.
2. b) Caine, D. Comprehensive Organic Synthesis, Vol. 3; Trost, B. M., Fleming, I., Eds.; Pergamon Press: Oxford, 1991; Chapter 1.1.
3. (2) a) Murakata, M.; Nakajima, M.; Koga, K. J. Chem. Soc., Chem. Commun. 1990, 1657-1658.
4. b) Murakata, M.; Yasukata, T.; Aoki, T.; Nakajima, M.; Koga, K. Tetrahedron 1998, 54, 2449-2458.
5. c) Imai, M.; Hagihara, A.; Kawasaki, H.; Manabe, K.; Koga, K. J. Am. Chem. Soc. 1994, 116, 8829-8830, and references cited therein.
6. (3) Matsuo, J.; Koga, K. Chem. Pharm. Bull. 1997, 45, 2122-2124.
7. (4) Trost, B. M.; Kunz, R. A. J. Org. Chem. 1974, 39, 2475-2476.
8. (5) Commercially available from Aldrich®. TMTHF can also be synthesized by refluxing a mixture of 2,5-dimethyl-2,5-hexanediol and dilute aqueous sulfuric acid.
9. (6) Judging from runs 3 and 11, and runs 10 and 12, prolonged reaction time caused decrease in enantioselectivity. In the case of TMTHF, less decrease was observed.
10. (7) Linstead, R. P.; Rydon, H. N. J. Chem. Soc. 1933, 580-586.
11. (8) In contrast to the alkylation of 1a, decrease in enantioselectivity was not observed under the prolonged reaction time.
12. (9) In THF-HMPA, high yield was realized using LDA. Herrmann, J. L.; Schlessinger, R. H. J. Chem. Soc., Chem. Commun. 1973, 711-712.
13. (10) Clarke, B. J.; Hildebrand, R. P. J. Inst. Brew. 1967, 75, 60-70.
14. 13 (equation presented)
15. (12) a) Helmchen, G.; Nill, G.; Flockerzi, D.; Youssef, M. S. K. Angew. Chem., Int. Ed. Engl. 1979, 18, 63-65.
16. b) Meyers, A. I.; Yamamoto, Y.; Mihelich, E. D.; Bell, R. J. Org. Chem. 1980, 45, 2792-2796.
17. 26= -26 (c 1.5, AcOEt). Cohen, S. G.; Milovanovic, A. J. Am. Chem. Soc. 1968, 90, 3495-3502.