Catalytic asymmetric synthesis of tertiary alkyl chlorides

Angewandte Chemie - International Edition

Volumn 46, Issue 6, 2007, Pages 977-979

  Lee, Elaine C ^a   McCauley, Kevin M ^a   Fu, Gregory C ^a  

^a MASSACHUSETTS INSTITUTE OF TECHNOLOGY   (United States)

Author keywords

Asymmetric catalysis; Chlorination; Ketenes

Indexed keywords

CATALYSIS; CATALYST ACTIVITY; CHLORINATION; SYNTHESIS (CHEMICAL);

ASYMMETRIC CATALYSIS; HALOCARBONYL COMPOUNDS; KETENES; TERTIARY ALKYL CHLORIDES;

OLEFINS;

EID: 33846660794     PISSN: 14337851     EISSN: None     Source Type: Journal    
DOI: 10.1002/anie.200604312     Document Type: Article

References (44)

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37. -1 from Aldrich). As far as we are aware, there are no reports of its use in catalytic asymmetric chlorination reactions.
38. See reference [10]. When we apply Lectka's method to the chlorination of phenyl ethyl ketene, the desired ester is produced in 30% yield and 5% ee.
39. N-Chloropyridines are known. For example, see: J. R. L. Smith, L. C. McKeer, J. M. Taylor, J. Chem. Soc. Perkin Trans. 2 1987, 1533-1537.
40. This mechanism resembles the Brønsted acid pathway that we have proposed for certain asymmetric additions to ketenes that are catalyzed by planar-chiral derivatives of DMAP (i.e., Cl takes the place of H). For example, see: S. L. Wiskur, G. C. Fu, J. Am. Chem. Soc. 2005, 127, 6176-6177.
41. [12]
42. [10]
43. For a review of nonlinear effects in asymmetric catalysis, see: H. B. Kagan, T. O. Luukas in Comprehensive Asymmetric Catalysis (Eds.: E.N. Jacobsen, A. Pfaltz, H. Yamamoto), Springer, New York, 1999, chap. 4.1.
44. Although we have not ruled out reaction by mean of a chiral chlorinating agent (top of Scheme 1), on the basis of circumstantial evidence (the stereochemical outcome, the reactivity profile, and the effect of concentration on ee), we favor the chiral-enolate pathway (bottom of Scheme 1).