622-67-3Relevant articles and documents
Catalytic Intermolecular C(sp3)-H Amination: Selective Functionalization of Tertiary C-H Bonds vs Activated Benzylic C-H Bonds
Brunard, Erwan,Boquet, Vincent,Van Elslande, Elsa,Saget, Tanguy,Dauban, Philippe
supporting information, p. 6407 - 6412 (2021/05/29)
A catalytic intermolecular amination of nonactivated tertiary C(sp3)-H bonds (BDE of 96 kcal·mol-1) is reported for substrates displaying an activated benzylic site (BDE of 85 kcal·mol-1). The tertiary C(sp3)-H bond is selectively functionalized to afford α,α,α-Trisubstituted amides in high yields. This unusual site-selectivity results from the synergistic combination of Rh2(S-Tfpttl)4, a rhodium(II) complex with a well-defined catalytic pocket, with tert-butylphenol sulfamate (TBPhsNH2), which leads to a discriminating rhodium-bound nitrene species under mild oxidative conditions. This catalytic system is very robust, and the reaction was performed on a 50 mmol scale with only 0.01 mol % of catalyst. The TBPhs group can be removed under mild conditions to afford the corresponding NH-free amines.
Method for decarboxylation and in-situ methylation of alkyl active carboxylic ester
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Paragraph 0047-0054; 0062-0068; 0203, (2020/06/20)
The invention relates to a method for decarboxylation and in-situ methylation of alkyl active carboxylic ester. The method comprises the following step: in the presence of a cobalt catalyst, a phosphine ligand and an organic solvent, reacting alkyl active carboxylic ester with a trimethyl aluminum reagent to obtain a target methylated product. According to the provided method, trimethyl aluminum is used as a methylation reagent, so that a series of important secondary carbon and tertiary carbon centers are commercially and conveniently constructed successfully; the used carboxylate substrate is rich in source and simple to synthesize; compared with a traditional synthesis method reported before, the method avoids the use of a noble metal catalyst, and meets the requirements of green environment-friendly chemistry; the functional group compatibility is wide, the method is successfully applied to gram-scale reaction, the conversion rate is high, and the method has an important syntheticchemical value.
Metallaphotoredox-Catalyzed Cross-Electrophile Csp3-Csp3 Coupling of Aliphatic Bromides
Smith, Russell T.,Zhang, Xiaheng,Rincón, Juan A.,Agejas, Javier,Mateos, Carlos,Barberis, Mario,García-Cerrada, Susana,De Frutos, Oscar,Macmillan, David W. C.
supporting information, p. 17433 - 17438 (2019/01/04)
A strategy for the installation of small alkyl fragments onto pharmaceutically relevant aliphatic structures has been established via metallaphotoredox catalysis. Herein, we report that tris(trimethylsilyl)silanol can be employed as an effective halogen abstraction reagent that, in combination with photoredox and nickel catalysis, allows a generic approach to Csp3-Csp3 cross-electrophile coupling. In this study, we demonstrate that a variety of aliphatic drug-like groups can be successfully coupled with a number of commercially available small alkyl electrophiles, including methyl tosylate and strained cyclic alkyl bromides. Moreover, the union of two secondary aliphatic carbon centers, a long-standing challenge for organic molecule construction, has been accomplished with a wide array of structural formats. Last, this technology can be selectively merged with Csp2-Csp3 aryl-alkyl couplings to build drug-like systems in a highly modular fashion.
