Solvent effects on the oxidative free radical reactions of 2-amino-1,4-naphthoquinones
作者:Chao-Ming Tseng、Yi-Lung Wu、Che-Ping Chuang
DOI:10.1016/j.tet.2004.10.029
日期:2004.12
Solvent effects on the manganese (III) initiatedoxidativefreeradicalreactions of 2-amino-1,4-naphthoquinones are described. This freeradicalreaction provides a novel method for the synthesis of benzo[f]indole-4,9-diones, benzo[f]indole-2,4,9-triones, benzo[b]carbazole-6,11-diones and benzo[b]acridine-6,11-diones. High chemoselectivity was observed in different solvents.
描述了溶剂对2-氨基-1,4-萘醌的锰(III)引发的氧化自由基反应的影响。该自由基反应为合成苯并[ f ]吲哚-4,9-二酮,苯并[ f ]吲哚-2,4,9-三酮,苯并[ b ]咔唑-6,11-二酮和苯并[ b ] ac啶-6,11-二酮。在不同溶剂中观察到高化学选择性。
Preparation of N-arylamines from 2-oxo-7-azobicyclo[4.1.0]heptanes
作者:M. Teresa Barros、Suvendu S. Dey、Christopher D. Maycock、Paula Rodrigues
DOI:10.1016/j.tet.2012.05.054
日期:2012.8
A wide range of N-phenylated secondary amines were prepared directly from 2-oxo-7-azobicyclo[4.1.0]heptanes using 4-nitrobenzoic acid as acid catalyst. The intermediate enol esters could also be isolated under similar conditions. A catalytic cycle is proposed.
The reaction of epoxides with lithiumhalides was efficiently promoted on the surface of silica gel in the absence of any solvent to give the corresponding β-halohydrins. The reactivity of lithiumhalides was shown to follow the order LiI> LiBr>> LiCl, and the reactivity of LiCl was dramatically increased by adding an equivalent amount of water to this system. On the other hand, a similar reaction
Reaction of cyclic α,β-epoxy ketones with Ce(III) chloride under hydrous or anhydrous conditions yields the corresponding cyclic α-chloro-α,β-enones or cyclic α-chloro-β-hydroxy ketones, respectively.
A mild preparation of α-halo-α,β-enones from cyclic enones
作者:Giuliana Righi、Paolo Bovicelli、Anna Sperandio
DOI:10.1016/s0040-4039(99)01213-7
日期:1999.8
A simple one pot procedure for the selective transformation of cyclic enones into cr-halo-a,P-enones is reported using dimethyldioxirane and metal halides / Amberlyst 15. The method appears particulary appealing for the preparation of labelled molecules for use with the CMIA techinique. (C) 1999 Published by Elsevier Science Ltd. All rights reserved.