1011-11-6Relevant articles and documents
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Smissman,E.E.,Pazdernik,T.L.
, p. 14 - 18 (1973)
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Verbit,Price
, p. 5143,5151 (1972)
Enantioselective acylation of rac-2-phenylcycloalkanamines catalyzed by lipases
Gonzalez-Sabin, Javier,Gotor, Vicente,Rebolledo, Francisca
, p. 3070 - 3076 (2007/10/03)
The kinetic resolution of some 2-phenylcycloalkanamines was performed by means of aminolysis reactions catalyzed by lipases, with Kazlauskas' rule being obeyed in all cases. The size of the ring and the stereochemistry of the stereogenic centers of the amines had a strong influence on both the enantiomeric ratio and the reaction rate of these aminolysis processes. Lipase B from Candida antarctica (CAL-B) showed excellent enantioselectivities toward trans-2-phenylcyclohexanamine in a variety of reaction conditions (E >150), whereas lipase A from C. antarctica (CAL-A) was the best catalyst for the acylation of cis-2-phenylcyclohexanamine (E = 34) and trans-2- phenylcyclopropanamine (E = 9).
Carbon-Skeletal Anionic Rearrangements of Tertiary Benzylic Amines: Geometric and Electronic Requirements for Generating the Spiroazacyclopropane Intermediate
Eisch, John J.,Dua, Suresh K.,Kovacs, Csaba A.
, p. 4437 - 4444 (2007/10/02)
In order to determine the scope and mechanism for the base-promoted rearrangement of tertiary amines, a wide variety of benzylic amines were treated with n-BuLi in THF or TMEDA, n-BuLi-KO-t-Bu mixtures, or KH.The following amines were examined: benzyldimethylamine, benzylmethylphenylamine, benzyldiphenylamine, N-benzylcarbazole, N-benzyl-1,2,3,4-tetrahydrocarbazole, N-benzyl-1,1a,2,3,4,4a-cis-hexahydrocarbazole, N-(2-phenylethyl)carbazole, N-(3-phenylpropyl)carbazole, N-(2-chloroethyl)carbazole, N-benzyl-9,9-dimethyl-9,10-dihydroacridine, N-benzyl-o,o'-iminodibenzyl, 9-(diphenylamino)fluorene, 9-anilino-9-phenylfluorene, 9-(methylphenylamino)fluorene, and diphenyl(diphenylmethyl)amine.In certain cases, ethylation products were obtained from the interaction of intermediate carbanions with ethylene generated by the decomposition of THF.The results are interpreted in terms of intramolecular shifts of aryl groups from nitrogen to benzylic carbon proceeding by way of a bridging aryl transition state or intermediate.