Synthesis of Functionalized Diaryldiazenes by Formal [3+3] Cyclizations of 1,3-Bis(silyloxy)-1,3-butadienes with 2-Aryldiazenyl-3-silyloxy-2-en-1- ones
The formal [3+3] cyclization of 1,3-bis(silyloxy)-1,3-butadienes with 2-aryldiazenyl-3-silyloxy- 2-en-1-ones afforded a variety of functionalized diaryl-diazenes.
Highly functionalized ferrocenyl-substituted phenols were prepared by cyclization of masked or free dianions with 1,3-dielectrophilic 1-η5-ferrocenyl-3,3-bis(methylthio)prop-2-en-1-ones. While the cyclizations of 1,3-bis(silyloxy)-1,3-butadienes (masked dianions) proceed by initial 1,2-addition, the reactions of free 1,3-dicarbonyl dianions proceed by initial 1,4-addition. Therefore, both regioisomeric
Regioselective [3+3] Cyclization of 1,3-Bis(silyloxy)buta-1,3-dienes with 1,1,1-Trifluoro-4-(silyloxy)alk-3-en-2-ones: New and Convenient Synthesis of Functionalized 5-Alkyl-3-(trifluoromethyl)phenols
作者:Stefan Büttner、Alina Bunescu、Sebastian Reimann、T. H. Tam Dang、Thomas Pundt、Renske Klassen、Andreas Schmidt、Nazken K. Kelzhanova、Zharylkasyn A. Abilov、Tariel V. Ghochikyan、Ashot S. Saghiyan、Alexander Villinger、Helmut Reinke、Anke Spannenberg、Peter Langer
DOI:10.1002/hlca.201200056
日期:2013.1
Functionalized 5‐alkyl‐3‐(trifluoromethyl)phenols were prepared by formal [3+3] cyclization of 1,3‐bis(silyloxy)buta‐1,3‐dienes with 1,1,1‐trifluoro‐4‐(silyloxy)alk‐3‐en‐2‐ones derived from 1,1,1‐trifluoroalkane‐2,4‐diones. The latter were prepared by condensation of the dianion of 1,1,1‐trifluoropentane‐2,4‐dione with alkyl halides.
Domino [3+3] Annulation/Ring-Cleavage Reactions of 1,3-Bis(trimethylsilyloxy)-1,3-butadienes with 5-Aryl- and 5-Vinyl-3-acyl- 4,5-dihydrofurans: Efficient Synthesis of 5-(4-Chlorobut-2-en-1-yl)- and 5-(2-Aryl-2-chloroethyl)salicylates
The domino “[3+3] cyclization–ring-opening” reactions of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with 3-acetyl-5-vinyl-4,5-dihydrofurans afforded 5-(4-halobut-2-en-1-yl)salicylates. The reactions of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with 3-acetyl-5-aryl-4,5-dihydrofurans gave 5-(2-aryl-2-chloroethyl)salicylates.
Synthesis of 9-Aryl-9,10-dihydrophenanthrenes by Domino [3+3] Annulation/Ring-Opening/Friedel-Crafts Alkylation Reactions of 1,3-Bis(trimethylsilyloxy)-1,3-butadienes with 3-Aroyl-5-aryl-4,5-dihydrofurans
The reaction of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with 3-benzoyl-5-aryl-4,5-dihydrofurans, available by CAN-mediated reaction of styrenes with benzoylacetones, afforded functionalized 9,10-dihydrophenanthrenes. These reactions proceed by a novel domino [3+3] cyclization/ring-opening/Friedel-Craftsalkylation process.