- Secondary Benzylation Using Benzyl Alcohols Catalyzed by Lanthanoid, Scandium, and Hafnium Triflate
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The combination of a secondary benzyl alcohol and a metal triflate (e.g., La, Yb, Sc, and Hf triflate) in nitromethane was a highly effective secondary-benzylation system. Secondary benzylation of carbon (aromatic compounds, olefins, an enol acetate), nitrogen (amide derivatives), and oxygen (alcohols) nucleophiles was carried out with a secondary benzyl alcohol and 0.01-1 mol % of a metal triflate in the presence of water. Secondary benzyl alcohols and nucleophiles bearing acid-sensitive functional groups (e.g., tert-butyldimethylsilyloxy and acetoxy groups and methyl and benzyl esters) could be used for alkylation. Hf(OTf)4 was the most active catalyst for this alkylation, and trifluoromethanesulfonic acid (triflic acid, TfOH) was also a good catalyst. The catalytic activity of metal triflates and TfOH increased in the order La(OTf)3 3 3 4. A mechanistic study was also performed. The reaction of 1-phenylethanol (4a) in the presence of Sc(OTf) 3 in nitromethane gave an equilibrium mixture of 4a and bis(1-phenylethyl) ether (54). Addition of a carbon nucleophile to the equilibrium mixture gave alkylated product in high yield.
- Noji, Masahiro,Ohno, Tomoko,Fuji, Koji,Futaba, Noriko,Tajima, Hiroyuki,Ishii, Keitaro
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Read Online
- Bottleable NiCl2(dppe) as a catalyst for the Markovnikov-selective hydroboration of styrenes with bis(pinacolato)diboron
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Although transition-metal-catalysed hydroboration reactions of alkenes have been extensively studied, only three examples using Ni complexes have been reported so far. In this study, we have examined hydroboration reactions of alkenes using Ni/phosphine complexes. The commercially available and bottleable complex NiCl2(dppe) (dppe = 1,2-bis(diphenylphosphino)ethane) serves as a catalyst for the highly Markovnikov-selective hydroboration of styrene derivatives that affords the desired Markovnikov products in high yield.
- Hashimoto, Toru,Ishimaru, Toshiya,Shiota, Keisuke,Yamaguchi, Yoshitaka
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supporting information
p. 11701 - 11704
(2020/10/20)
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- BRM TARGETING COMPOUNDS AND ASSOCIATED METHODS OF USE
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The present disclosure relates to bifunctional compounds, which find utility as modulators of SMARCA2 or BRM (target protein). In particular, the present disclosure is directed to bifunctional compounds, which contain on one end a ligand that binds to the Von Hippel-Lindau E3 ubiquitin ligase, and on the other end a moiety which binds the target protein, such that the target protein is placed in proximity to the ubiquitin ligase to effect degradation (and inhibition) of target protein. The present disclosure exhibits a broad range of pharmacological activities associated with degradation/inhibition of target protein. Diseases or disorders that result from aggregation or accumulation of the target protein are treated or prevented with compounds and compositions of the present disclosure.
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Paragraph 1075-1076
(2019/10/23)
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- Facile preparation of α-aryl nitriles by direct cyanation of alcohols with TMSCN under the catalysis of InX3
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(Chemical Equation Presented) A convenient and efficient synthesis of α-aryl nitrites was developed by direct cyanation of alcohols with TMSCN under the catalysis of Lewis acid. Using 5-10 mol % of InBr3 as the catalyst, a variety of benzylic alcohols can be converted to the corresponding nitriles in 5-30 min with yields of 46-99%.
- Chen, Gang,Wang, Zheng,Wu, Jiang,Ding, Kuiling
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supporting information; experimental part
p. 4573 - 4576
(2009/05/07)
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