Regioselective construction of diverse and multifunctionalized 2-hydroxybenzophenones for sun protection by indium(<scp>iii</scp>)-catalyzed benzannulation
作者:Hongyun Cai、Likai Xia、Yong Rok Lee
DOI:10.1039/c6cc02381a
日期:——
Highly regioselective synthesis of 2-hydroxybenzophenones via the In(OTf)3-catalyzed formal [2+2+2] and [4+2] benzannulations has been successfully developed and their application as sun protection materials was also evaluated.
The imino Diels–Alderreaction is an efficient method for the synthesis of aza‐heterocycles. While different stereo‐ and enantioselective inverse‐electron‐demand imino Diels–Alder (IEDIDA) reactions have been reported before, IEDIDA reactions including electron‐deficient dienes are unprecedented. The first enantioselective IEDIDA reaction between electron‐poor chromone dienes and cyclic imines, catalyzed
Domino reactions of 2-methyl chromones containing an electron withdrawing group with chromone-fused dienes
作者:Jian Gong、Fuchun Xie、Wenming Ren、Hong Chen、Youhong Hu
DOI:10.1039/c1ob06613g
日期:——
Domino reactions of 2-methyl substituted chromones containing an electronwithdrawinggroup at the 3-position with chromone-fused dienes synthesized a diverse range of benzo[a]xanthones and complicated chromone derivatives. These multiple-step reactions result in either two or three new C–C bonds without a transition metal catalyst or an inert atmosphere.
在3位上具有吸电子基团的2-甲基取代的色酮与色酮稠合的二烯的多米诺反应合成了多种苯并[ a ]氧杂蒽酮和复杂的色酮衍生物。这些多步反应可产生两个或三个新的C–C键,而无需过渡金属催化剂或惰性气氛。
Domino Reaction to Functionalized 2-Hydroxybenzophenones from Electron-Deficient Chromones and 1,3-Dicarbonyl Compounds
作者:Hong Chen、Fuchun Xie、Jian Gong、Youhong Hu
DOI:10.1021/jo201384f
日期:2011.10.21
A base-promoted one-pot tandemreaction sequence has been developed to transform electron-deficient chromone-fused dienes 1 and 1,3-dicarbonylcompounds 2 to functionalized 2-hydroxybenzophenones 3 under mild conditions. This domino process, which involves multiple reactions, including Michael addition/cyclization/elimination, serves as an efficient, economic, and eco-friendly method for the construction
Cascade reactions between 2-substituted-3-(4-oxo-4H-chromen-3-yl)acrylonitriles with benzylamine and p-toluidine
作者:Magdy A. Ibrahim、Al-Shimaa Badran
DOI:10.24820/ark.5550190.p010.745
日期:——
Abstract Chemical transformations of the simple condensation products derived from 3-formylchromone and some active methylene compounds, was achieved by reaction with nucleophilicreagents namely benzylamine and p-toluidine to produce either 2-iminopyrane or pyrano[3,2-c]chromene derivatives. These transformations initially proceed through nucleophilic attack at C-2 of the γ–pyrone ring with concomitant