Manganese (II) catalysed Hunsdiecker reaction: A facile entry to α-(dibromomethyl) benzenemethanol
作者:Shantanu Chowdhury、Sujit Roy
DOI:10.1016/0040-4039(96)00343-7
日期:1996.4
Manganese (II) acetate catalysed reactions of α,β - unsaturated aromatic carboxylic acids 1 with NBS (1 and 2 eq.) in MeCN / water afford haloalkenes 2 and α-(dibromomethyl) benzenemethanols 3 respectively.
Catalytic Hunsdiecker Reaction and One-Pot Catalytic Hunsdiecker–Heck Strategy: Synthesis of α,β-Unsaturated Aromatic Halides, α-(Dihalomethyl)benzenemethanols, 5-Aryl-2,4-pentadienoic acids, Dienoates and Dienamides
作者:Dinabandhu Naskar、Sujit Roy
DOI:10.1016/s0040-4020(99)01035-2
日期:2000.3
The reaction of α,β-unsaturated aromatic (or heteroaromatic) carboxylic acids with N-halosuccinimides (1 equiv.) and catalytic tetrabutylammonium trifluoroacetate (0.2 equiv.) in dichloroethane results in facile halodecarboxylation affording the corresponding (E)-halides in good to excellent yields. A similar reaction, but with 2 equiv. of N-halosuccinimides in acetonitrile-water (1:1 v/v) results
α,β-不饱和芳族(或杂芳族)羧酸与N-卤代琥珀酰亚胺(1当量)和催化四丁基三氟乙酸铵(0.2当量)在二氯乙烷中的反应导致容易的卤代羧化,从而得到相应的(E)-卤化物优异的产量。类似的反应,但具有2当量。的N在乙腈-水中(1-1:1 v / v)中的-卤代琥珀酰亚胺导致相应的α-(二卤代甲基)苯甲醇的排他性形成。此外,已开发出一种结合了Hunsdiecker催化反应(在二氯乙烷中使用三氟乙酸四丁基铵)和Heck偶联(使用乙酸钯/三乙胺/三苯基锑/二氯乙烷)的一锅法,用于合成5-芳基-2,4-戊二烯酸,酯和酰胺,产率中等至良好。通过上述途径合成了天然产物胡椒碱和哌瓜胺。机理和理论研究(通过AM1计算)对当前的卤代羧化反应的机理提供了有用的见解,表明离子途径涉及卤离子跨碳-碳双键的攻击,
Secondary Benzylation with Benzyl Alcohols Catalyzed by A High-Valent Heterobimetallic Ir−Sn Complex
作者:Susmita Podder、Joyanta Choudhury、Sujit Roy
DOI:10.1021/jo0625094
日期:2007.4.1
A highly efficient secondary benzylation procedure has been demonstrated using a high-valent heterobimetallic complex [Ir2(COD)2(SnCl3)2(Cl)2(μ-Cl)2] 1 as the catalyst in 1,2-dichloroethane to afford the corresponding benzylated products in moderate to excellent yields. The reaction was performed not only with carbon nucleophiles (arenes and heteroarenes) but also with oxygen (alcohol), nitrogen (amide