Diastereoselective reaction of [1-(2,4,6-triisopropylphenylsulfinyl)-2-naphthyl]methanimines via diastereomeric rotamers
摘要:
The reactions of various (1-sulfinyl-2-naphthyl)methanimines with alkyllithium reagents were examined. Naphthylmethanimines bearing a 2,4,6-triisopropylphenylsulfinyl group gave the (R*(S), S*)-products as a single diastereomer, possibly derived from the predominant rotamer around the C-S bond axis. The reaction of chiral [1-(2,4,6-triisopropylphenylsulfinyl)-2-naphthyl]methanimine with MeLi and subsequent elimination of the sulfinyl group afforded optically active 1-(2-naphthyl)ethylamine. (C) 2002 Elsevier Science Ltd. All rights reserved.
The reaction of 1-[(2,4,6-triisopropylphenyl)sulfinyl]-2-naphthaldehyde with (trifluoromethyl)trimethylsilane using tetramethylammonium fluoride gave trifluoromethylated compounds in high yield with high diastereoselectivity. Desilylation and subsequent recrystallization yielded the enantiomerically and diastereomerically pure trifluoroethanol, which afforded chiral 1-(2-naphthyl)-2,2,2-trifluoroethanol