An efficient organocatalytic quadruple cascadereaction resulting in spiroxindole scaffolds bearing five quaternary stereocenters is reported. The complex cascadereaction is triggered by the scarcely explored vinylogous Michael addition of 3-alkylidene oxindoles to fullysubstituted enones and demonstrates the usefulness of the latter as efficient Michael acceptors in generating complex caged products
An expedient synthesis of 3-alkylideneoxindoles by Ti(O Pr)4/pyridine-mediated Knoevenagel condensation
作者:Hyun Ju Lee、Jin Woo Lim、Jin Yu、Jae Nyoung Kim
DOI:10.1016/j.tetlet.2013.12.097
日期:2014.2
3-Alkylideneoxindoles have been prepared in excellent yields from oxindole and carbonyl compounds via an in situ generated titanium enolate of oxindole. (Z)-3-Alkylideneoxindoles could be synthesized selectively as major products from unsymmetrical ketones. (C) 2014 Elsevier Ltd. All rights reserved.
Vinylogous N,N-dimethylaminomethylenation of 3-[(1-substituted)ethylidene]-oxindoles with N,N-dimethylformamide dimethylacetal
作者:Hyun Ju Lee、Sangku Lee、Jin Yu、Jae Nyoung Kim
DOI:10.1016/j.tetlet.2014.02.130
日期:2014.4
An efficient stereoselective synthesis of various 3-(3-dimethylaminoprop-2-enylidene)oxindoles has been disclosed. The compounds were synthesized via a vinylogous N,N-dimethylaminomethylenation at the gamma-position of 3-[(1-substituted)ethylidene]oxindoles with DMF-DMA. (C) 2014 Elsevier Ltd. All rights reserved.