The study of catalyst free and copper catalyzed reactions of cyanochromenes and sodium azide
摘要:
Two different roles of sodium azide under two different conditions are described here along with the plausible mechanisms. When sodium azide was treated with cyanochromenes under catalyst free conditions, the azide anion acted as a base. Hence, a base mediated rearrangement of cyanochromenes was resulted in formation of benzofuran derivatives. However, in the presence of catalytic amount of CuI the azide anion acted as a diene to produce chromenotetrazoles. (C) 2013 Elsevier Ltd. All rights reserved.
A Convenient Baylis-Hillman Synthesis of 3-Substituted 2<b><i>H</i></b>-1-Benzothiopyrans
作者:Perry Kaye、Xolani Nocanda
DOI:10.1055/s-2001-18704
日期:——
Reaction of 2,2"-dithiodibenzaldehyde 1 with activated alkenes 2a-g in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) affords, in one step, 3-substituted 2H-1-benzopyrans 6a-g in yields of up to 67%.
One-pot synthesis of 2<i>H</i>-thiochromenes<i>via</i>TiCl<sub>4</sub>-promoted reaction of 2-<i>tert</i>-butylthiobenzaldehydes with activated alkenes
作者:Chang Hoon Lee、Kee-Jung Lee
DOI:10.1002/jhet.182
日期:2009.9
A facile synthesis of 2H-thiochromenes through TiCl4-promoted reaction of 2-tert-butylthiobenzaldehydes with activatedalkenes is described. J. Heterocyclic Chem., (2009).
NOVEL CHROMENE AND THIOCHROMENE CARBOXAMIDE DERIVATIVES, METHODS FOR PREPARING SAME AND THERAPEUTIC APPLICATIONS OF SAME
申请人:Sokoloff Pierre
公开号:US20100029682A1
公开(公告)日:2010-02-04
The present invention relates to novel chromene or thiochromene carboxamide derivatives, the preparation of same, pharmaceutical compositions of same and the use of same as dopamine D3 ligands as a medicament for central nervous system disorders.
Dual-Catalyst Acceleration of Tandem Disulfide Cleavage and Baylis–Hillman Synthesis of 2<i>H</i>-1-Benzothiopyran Derivatives
作者:Dubekile Nyoni、Kevin A. Lobb、Perry T. Kaye
DOI:10.1080/00397911.2012.673449
日期:2013.7.3
While both 1,8-diazabicyclo[5.4.0]undec-7-ene and triphenylphosphine catalyze tandem Baylis-Hillman reaction/disulfide cleavage of 2,2'-dithiodibenzaldehyde independently, when used together as a dual-catalyst system, the overall yields of the cyclized 2H-1-benzothiopyrans are consistently greater and the reaction time decreases dramatically.Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications (R) to view the free supplemental file.