A mild, convenient, and inexpensive method for converting imines into amines: Tin-catalyzed reduction with polymethylhydrosiloxane (PMHS)
作者:Rosa M. Lopez、Gregory C. Fu
DOI:10.1016/s0040-4020(97)01020-x
日期:1997.12
protocol for reducing imines to amines. Thus, treatment of any of a wide array of imines with catalytic n-butyltris(2-ethylhexanoate)tin and stoichioimetric polymethylhydrosiloxane (PMHS) in ethanol at room temperature cleanly affords the desired secondary amine product. Alkyl bromides, alkynes, epoxides, esters, nitriles, and olefins are inert toward these reduction conditions, whereas aldehydes, ketones
N-Mesyloxylactams can undergo ring contraction either by C-3 (usually observed) or C-5 migration. C-5 migration can occur when the C-3 migration product possesses ring strain, but it does not usually compete with C-3 migration. The greater preference for C-3 migration is due to the carbonyl oxygen atom, which greatly stabilizes the intermediate.