Nickel-Catalyzed Arylation of C(sp<sup>3</sup>)–O Bonds in Allylic Alkyl Ethers with Organoboron Compounds
作者:Xiaowei Li、Yuxiu Li、Zhong Zhang、Xiaolin Shi、Ruihua Liu、Zemin Wang、Xiangqian Li、Dayong Shi
DOI:10.1021/acs.orglett.1c01879
日期:2021.9.3
A nickel-catalyzed cross-coupling of allylic alkyl ethers with organoboron compounds through the cleavage of the inert C(sp3)-O(alkyl) bonds is described. Several types of allylic alkyl ethers can be coupled with various boronic acids or their derivatives to give the corresponding products in good to excellent yields with wide functional group tolerance and excellent regioselectivity. The gram-scale
Brønsted Acid-Catalyzed Intramolecular Hydroarylation of β-Benzylstyrenes
作者:Xiao Cai、Amir Keshavarz、Justin D. Omaque、Benjamin J. Stokes
DOI:10.1021/acs.orglett.7b00958
日期:2017.5.19
triphenylmethylium tetrakis(pentafluorophenyl)borate as a convenient Brønsted acid precatalyst, β-(α,α-dimethylbenzyl)styrenes are shown to cyclize efficiently to afford a variety of new indanes that possess a benzylic quaternary center. The geminal dimethyl-containing quaternary center is proposed to be necessary to arm the substrate for cyclization through steric biasing.
Enantiospecific, Regioselective Cross-Coupling Reactions of Secondary Allylic Boronic Esters
作者:Laetitia Chausset-Boissarie、Kazem Ghozati、Emily LaBine、Jack L.-Y. Chen、Varinder K. Aggarwal、Cathleen M. Crudden
DOI:10.1002/chem.201303683
日期:2013.12.23
enantioselective Suzuki–Miyaura cross‐coupling of chiral, enantioenriched secondaryallylic boronic esters is described (see scheme; DME=dimethoxyethane, Bpin = pinacolboryl, dba = dibenzylideneacetone). Mechanistic studies show that the reactions proceed via γ‐selective transmetalation followed by reductive elimination. The reaction provides the first independent confirmation that the transmetalation of
The phenyldimethylsilyl group as a masked form of the hydroxy group
作者:Ian Fleming、Rolf Henning、Howard Plaut
DOI:10.1039/c39840000029
日期:——
The phenyldimethylsilylgroup can be converted in two steps, protodesilylation and peracid-mediated rearrangement, into a hydroxygroup with retention of configuration: β-phenyldimethylsilyl carbonyl compounds are thus revealed to be masked aldol products.
The reaction of styrene with α-methylstyrene has been studied over Y, Beta and ZSM-12 zeolites at 80–120 °C in the presence or absence of chlorobenzene. Homo- and codimers of styrene and α-methylstyrene were the main reaction products. The yield of dimers and their structure depends on zeolite type and the experimental conditions. Dimers were formed with greater selectively over zeolite HZSM-12 (S = 80–83%)