Raising the p<i>K</i><sub>a</sub> Limit of “Soft” Nucleophiles in Palladium-Catalyzed Allylic Substitutions: Application of Diarylmethane Pronucleophiles
作者:Sheng-Chun Sha、Jiadi Zhang、Patrick J. Carroll、Patrick J. Walsh
DOI:10.1021/ja409511n
日期:2013.11.20
Tsuji-Trost allylicsubstitution reaction provides a useful and efficient approach to construct C-C bonds between sp(3)-hybridized carbons. The widely accepted paradigm for classifying the mode of attack of nucleophiles on palladium π-allyl intermediates in the Tsuji-Trost reaction is based on the pKa of the pronucleophile: (1) stabilized or "soft" carbonnucleophiles and heteroatom nucleophiles (e.g.,
Nickel‐Catalyzed Allylic Alkylation with Diarylmethane Pronucleophiles: Reaction Development and Mechanistic Insights
作者:Sheng‐Chun Sha、Hui Jiang、Jianyou Mao、Ana Bellomo、Soo A. Jeong、Patrick J. Walsh
DOI:10.1002/anie.201507494
日期:2016.1.18
Palladium‐catalyzedallylicsubstitution reactions are among the most efficientmethods to construct C−C bonds between sp3‐hybridized carbon atoms. In contrast, much less work has been done with nickel catalysts, perhaps because of the different mechanisms of the allylicsubstitution reactions. Palladium catalysts generally undergo substitution by a “soft”‐nucleophile pathway, wherein the nucleophile attacks
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
Scandium as a pre-catalyst for the deoxygenative allylation of benzylic alcohols
作者:Ivan Šolić、Pattarakiat Seankongsuk、Joanna Kejun Loh、Tirayut Vilaivan、Roderick W. Bates
DOI:10.1039/c7ob02219k
日期:——
pre-catalyst for the deoxygenative allylation of benzylic alcohols with a narrow substrate window. The reaction is shown to proceed through a “hidden Brønsted acid” mechanism. The reaction is efficient provided that the aryl group is neither too electron rich nor too electron poor. It is shown that this allows useful selectivity. The reaction also works for benzyhydryl alcohols with broader scope. The reaction
Facile Direct Coupling Reactions of
<scp>MOM</scp>
‐protected Benzylic Alcohols Using Aluminum Chloride
作者:Tien Tan Bui、Hee‐Kwon Kim
DOI:10.1002/bkcs.12358
日期:2021.9
used protecting groups for alcohols. This study describes novel direct functionalization of the MOM-protected benzylic alcohols. Preparation of allylic compounds from benzyl MOM ethers was successfully achieved by utilization of allyltrimethylsilane and AlCl3. In addition, direct azidation of benzyl MOM ethers using TMSN3 was successful carried out under AlCl3-mediated reaction conditions. These results