Chirality transfer during alkylation of chiral amides

Chemical Communications

Volumn , Issue 1, 2003, Pages 162-163

  Kawabata, Takeo ^a   Öztürk, Orhan ^a   Chen, Jianyong ^a   Fuji, Kaoru ^a  

^a KYOTO UNIVERSITY   (Japan)

Author keywords

[No Author keywords available]

Indexed keywords

AMIDE; MANDELIC ACID DERIVATIVE; METHYL IODIDE; O METHYLMANDELIC ACID; UNCLASSIFIED DRUG;

ALKYLATION; ARTICLE; CHIRALITY; ENANTIOSELECTIVITY; METHYLATION; POLYMERIZATION; PROTON TRANSPORT; STEREOCHEMISTRY;

EID: 0037222246     PISSN: 13597345     EISSN: None     Source Type: Journal    
DOI: 10.1039/b209736b     Document Type: Article

References (19)

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5. Chiral properties ofA are time- and temperature-dependent. Therefore, we denote this type of chirality 'dynamic chirality'. The half-life to racemization ofA is 22 h at -278°C, see: T. Kawabata, H. Suzuki, Y. Nagae and K. Fuji, Angew. Chem., Int. Ed., 2000, 39, 2155; T. Kawabata, J. Chen, H. Suzuki, Y. Nagae, T. Kinoshita, S. Chancharunee and K. Fuji, Org. Lett., 2000, 2, 3883; T. Kawabata, S. Kawakami and K. Fuji, Tetrahedron Lett., 2002, 43, 1465.
6. Chiral properties ofA are time- and temperature-dependent. Therefore, we denote this type of chirality 'dynamic chirality'. The half-life to racemization ofA is 22 h at -278°C, see: T. Kawabata, H. Suzuki, Y. Nagae and K. Fuji, Angew. Chem., Int. Ed., 2000, 39, 2155; T. Kawabata, J. Chen, H. Suzuki, Y. Nagae, T. Kinoshita, S. Chancharunee and K. Fuji, Org. Lett., 2000, 2, 3883; T. Kawabata, S. Kawakami and K. Fuji, Tetrahedron Lett., 2002, 43, 1465.
7. Chiral properties ofA are time- and temperature-dependent. Therefore, we denote this type of chirality 'dynamic chirality'. The half-life to racemization ofA is 22 h at -278°C, see: T. Kawabata, H. Suzuki, Y. Nagae and K. Fuji, Angew. Chem., Int. Ed., 2000, 39, 2155; T. Kawabata, J. Chen, H. Suzuki, Y. Nagae, T. Kinoshita, S. Chancharunee and K. Fuji, Org. Lett., 2000, 2, 3883; T. Kawabata, S. Kawakami and K. Fuji, Tetrahedron Lett., 2002, 43, 1465.
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12. 2O led to the production of 2 in 5% ee or 37% ee, respectively.
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17. Several attempts at improving the yield of a-methylation were unsuccessful: e.g. prolonged enolate-formation (30-120 min), higher temperature (-260°C) for enolate formation and/or methylation
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