6-烷氧基-3-芳基-6-三甲基甲硅烷氧基-5,6-二氢-4 H -1,2-恶嗪的合成及其酸催化水解反应生成3-芳基-5,6-二氢-4 H -1 ,2-恶嗪-6-和/或4-芳基-4-(羟基亚氨基)丁酸酯
摘要:
由α-氯苯乙酮肟及其环取代的衍生物与K 2 CO 3在四氢呋喃中的反应生成的α-亚硝基苯乙烯及其环取代的衍生物与乙烯酮三甲基甲硅烷基乙缩醛的环加成反应得到6-烷氧基-3 -芳基-6-三甲基甲硅烷氧基-5,6-二氢-4 H -1,2-恶嗪。这些恶嗪易受盐酸催化的水解,得到3-芳基-5,6-二氢-4 H -1,2-恶嗪6-1和/或4-芳基-4-(羟基亚氨基)丁酸酯。
InBr
<sub>3</sub>
‐Catalyzed Coupling Reaction between Electron‐Deficient Alkenyl Ethers with Silyl Enolates for Stereoselective Synthesis of 1,5‐Dioxo‐alk‐2‐enes
InBr3 catalysis enables the coupling between 2‐carbonylalkenyl ethers and silyl enolates to give 1,5‐dioxo‐alk‐2‐enes featuring alkene moieties with perfect stereoselectivity. Various types of 2‐carbonylalkenyl ethers and silyl enolates are applicable to the present reaction. InBr3 with moderate Lewis acidity plays an important role in both the activation of alkenyl ethers and in the elimination of
Regioselective Carboindation of Simple Alkenes with Indium Tribromide and Ketene Silyl Acetals
作者:Yoshihiro Nishimoto、Hiroki Ueda、Yoshihiro Inamoto、Makoto Yasuda、Akio Baba
DOI:10.1021/ol1012108
日期:2010.8.6
The regioselective carboindation of simplealkenes with indium tribromide and ketene silyl acetals was accomplished. Various alkenes such as ethylene, 1-alkenes, and cyclic alkenes were applicable for this reaction system. The alkylindium product from the carboindation of cyclohexene revealed an anti addition mechanism.
(Z)-β-Aryloxyalkenylzincs are synthesized stereoselectively via anti-carbozincation among alkynyl ethers, silyl ketene acetals, and ZnBr2. X-ray analysis revealed the structure of the zinc species is a mononuclear two-coordinate dialkenylzinc that is transformed into functionalized enol ethers as a single isomer in the reaction of various electrophiles.
Carboboration‐Driven Generation of a Silylium Ion for Vinylic C−F Bond Functionalization by B(C
<sub>6</sub>
F
<sub>5</sub>
)
<sub>3</sub>
Catalysis
作者:Tetsuji Yata、Yoshihiro Nishimoto、Makoto Yasuda
DOI:10.1002/chem.202103852
日期:2022.2
B(C6F5)3-catalyzed reactions between fluoroalkenes and silyl ketene acetals gave vinylic C−F bond-functionalized products under mild and simple conditions. Carboboration reaction of fluoroalkenes generates an oxygen-stabilized silylium ion to facilitate the C−F bond cleavage. DFT and IBO studies were performed to clear the reaction mechanism. A comparative study of α-chloro or bromostyrenes demonstrated
Syntheses of Aldol Products and Cyanohydrins from Carboxylic Acids Using Hydrosilanes, Organosilicon Reagents, and Indium Triiodide Catalyst
作者:Yoshihiro Inamoto、Yoshihiro Nishimoto、Makoto Yasuda、Akio Baba
DOI:10.1246/cl.130790
日期:2013.12.5
Carboxylic acids were applied to an indium triiodide-catalyzed reductive aldol reaction and a reductive cyanation in order to produce aldol adducts and cyanohydrins, respectively, in which the separate addition of two kinds of hydrosilanes was crucial in combination with either ketene silyl acetals or silyl cyanides.