A Convenient Synthesis of 1-Alkyl-1-phenylhydrazines fromN-Aminophthalimide
摘要:
N-Alkylaminophthalimides were synthesized by condensation of N-aminophthalimide with aldehydes, and subsequent reduction of the intermediate with pyridine-borane in acetic acid. N-Phenylation and removal of the phthalimide group gave 1-alkyl-1-phenylhydrazines in high yield.
Reductive Hydrazination with Trichlorosilane: A Method for the Preparation of 1,1-Disubstituted Hydrazines
作者:Tao Wang、Xiao Di、Chao Wang、Li Zhou、Jian Sun
DOI:10.1021/acs.orglett.6b00675
日期:2016.4.15
and facile method has been developed to prepare 1,1-disubstituted hydrazines via Lewis base promoted direct reductive hydrazination. Under the catalysis of hexamethylphosphoramide (HMPA) and N,N-dimethylacetamide (DMAc), respectively, various ketones and aldehydes could react with phenylhdrazines to prepare 1,1-disubstituted hydrazines with good to high yields.
The asymmetric totalsynthesis of vinorine, a polycyclic and cage-like alkaloid, has been realized in a flexible approach. Key features of the current synthesis include an aza-Achmatowicz rearrangement/Mannich-type cyclization to install the highly functional 9-azabicyclo-[3.3.1]nonane scaffold, a high yield Fischer indole annulation to synthesize the common intermediate for sarpagine-ajamaline type
We present a PPh3/DDQ-mediated regiospecific selectiveN-functionalization of arylhydrazines with primary benzylic alcohols and aryl carboxylic acids for the synthesis of N1-benzyl arylhydrazines and N2-acyl arylhydrazines, respectively. This metal- and base-free approach features very short reaction times (about 10 min), broad substrate scope, good functional group tolerance, and mild reaction conditions