Synthesis of Hydrazine Derivatives
An environmentally benign, tin-free radical "on water" addition of alkyl iodides to the C=N bond of hydrazones in the presence of diphenylsilane and triethylborane afforded the corresponding addition products in good yields. The developed protocol can be applied to the synthesis of 3-substituted isoindolinone derivatives.
T. K. Nam, D. O. Jang, J. Org. Chem., 2018, 83, 7373-7379.
Cu-catalyzed and metal-free conditions developed for allyltrimethoxysilane addition to N-benzoylhydrazones enable efficient and versatile access to homoallylic α-branched amines. Aldehyde hydrazones, both aromatic and aliphatic, and ketone hydrazones all give good yields.
H. Ding, G. K. Friestadt, Synthesis, 2004, 2216-2221.
The reaction of allylboronic acids with acyl hydrazones proceeds with very high syn selectivity to afford homoallylic amine derivatives. The reaction can be carried out with both aromatic and aliphatic acyl hydrazones. The excellent syn stereochemistry, which is the opposite of the stereochemistry observed for allylboration of imines, can be explained by chelation control of the acyl hydrazone and the B(OH)2 moiety.
A. Das, R. Alam, L. Eriksson, K. J. Szabo, Org. Lett., 2014, 16, 3808-3811.