Kinetic resolutions of lndolines by a nonenzymatic acylation catalyst

Journal of the American Chemical Society

Volumn 128, Issue 44, 2006, Pages 14264-14265

  Arp, Forrest O ^a   Fu, Gregory C ^a  

^a MASSACHUSETTS INSTITUTE OF TECHNOLOGY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

2 METHYLINDOLINE; 2 OXAZOLIDINONE DERIVATIVE; AMINE; INDOLE DERIVATIVE; INDOLINE DERIVATIVE; UNCLASSIFIED DRUG; INDOLINE;

ACYLATION; ARTICLE; CATALYST; CHEMICAL REACTION; CHEMICAL REACTION KINETICS; CHEMICAL STRUCTURE; CHIRALITY; ENANTIOMER; QUANTUM YIELD; REACTION ANALYSIS; REACTION TIME; ROOM TEMPERATURE; STOICHIOMETRY; CATALYSIS; CHEMICAL MODEL; CHEMISTRY; HYDROGEN BOND; KINETICS; STEREOISOMERISM; SYNTHESIS; TEMPERATURE;

ACYLATION; CATALYSIS; HYDROGEN BONDING; INDOLES; KINETICS; MODELS, CHEMICAL; MOLECULAR STRUCTURE; STEREOISOMERISM; TEMPERATURE;

EID: 33750685325     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja0657859     Document Type: Article

References (31)

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24. Clearly, long reaction times are not ideal. On the other hand, this kinetic-resolution method avoids protection/deprotection of the indole, which is necessary for the most general alternative approach to the catalytic synthesis of enantionriched indolines (ref 3a).
25. 2-hybridized, low selectivity is observed.
26. (a) However, an indoline that bears two electronegative fluorine substituents (4,5-difluoro-2-methylindoline) reacts very slowly and with moderate selectivity (s ≈ 7).
27. (b) Catalyst 1 can be recovered in good yield (> 80%).
28. We have been able to achieve the kinetic resolution of a 2-substituted pyrrolidine with s ≈ 4. To the best of our knowledge, this is the first example of a kinetic resolution of a dialkylamine with promising selectivity by a nonenzymatic acylation catalyst.
29. Preliminary studies of the dependence of the selectivity factor on the catalyst ee provide no evidence for the presence of species that contain more than one catalyst molecule. (a) Johnson, D. W., Jr.; Singleton, D. A. J. Am. Chem. Soc. 1999, 121, 9307-9312.
30. (b) Kagan, H. B.; Luukas, T. O. In Comprehensive Asymmetric Catalysis; Jacobsen, E. N., Pfaltz, A., Yamamoto, H., Eds.; Springer: New York, 1999; Chapter 4.1.
31. This may be a consequence of the enhanced acidity of the N-bound proton of an indoline, relative to a primary benzylic amine.