Trifluoroacetyl-Activated Nitrogen−Nitrogen Bond Cleavage of Hydrazines by Samarium(II) Iodide
摘要:
Trifluoroacetyl derivatives of hydrazines undergo clean and efficient reductive cleavage of the N-N bond with SmI2 in the presence of MeOH. After N-trifluoroacetylation, acyl-, aryl-, and alkyl-substituted hydrazines are reductively cleaved by this method to afford trifluoroacetamides in yields ranging from 70 to 96%. These conditions accommodate alkene functionality, avoid racemization, and furnish chiral amines bearing a readily removable TFA protecting group.
BF3-promoted hydrostannation of N-heteroatom-substituted imines for the reduction of CN bond
摘要:
Hydrostannation of n-heteroatom-substituted imines such as oxime ethers, hydrazones, oximes, nitrones, and V-sulfonyl imines using a combination of Bu3SnH and (BF3OEt2)-O-. has been systematically studied. Not only aromatic aldimines but also kitimines and aliphatic imines were reduced to give the corresponding amines. (C) 2002 Elsevier Science Ltd. All rights reserved.