863780-45-4Relevant academic research and scientific papers
Facile Hydrogenolysis of C(sp3)–C(sp3) σ Bonds
Fillion, Eric,Beaton, Eric,Nguyen, Yen,Wilsily, Ashraf,Bondarenko, Ganna,Jacq, Jér?me
supporting information, p. 3422 - 3434 (2016/11/13)
The modification of benzylic quaternary, tertiary, and secondary carbon centers through palladium-catalyzed hydrogenolysis of C(sp3)–C(sp3) σ bonds is presented. When benzyl Meldrum's acid derivatives bearing quaternary benzylic centers are treated under mild hydrogenolysis conditions – palladium on carbon and atmospheric pressure of hydrogen – aromatics substituted with tertiary benzylic centers and Meldrum's acid are obtained with good to excellent yield. Analogously, substrates containing tertiary or secondary benzylic centers yield aromatics substituted with secondary benzylic centers or toluene derivatives, respectively. Furthermore, this strategy is used for the high yielding synthesis of diarylmethanes. The scope of the reductive dealkylation reaction is explored and the limitations with respect to steric and electronic factors are determined. A mechanistic analysis of the reaction is described that consisted of deuterium labelling experiments and hydrogenolysis of enantioenriched derivatives. The investigation shows that the C(sp3)–C(sp3) σ bond-cleaving events occur through a hybrid SN1/SN2 mechanism, in which the palladium center displaces a carbon-based leaving group, namely Meldrum's acid, with inversion of configuration, followed by reductive elimination of palladium to furnish a C?H bond. (Figure presented.).
Process for producing α-arylalkanoic acid ester
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, (2008/06/13)
A process for producing an α-arylalkanoic acid ester represented by the general formula STR1 wherein Ar represents an aryl group which may optionally be substituted, and R1 and R2, independently from each other, represent a lower alkyl group, which comprises reacting a Grignard reagent prepared from an aryl halide of the general formula wherein Ar is as defined above and X1 represents a halogen atom, and magnesium, with an α-haloalkanoic acid ester of the general formula STR2 wherein R1 and R2 are as defined above, and X2 represents a halogen atom, said reaction of the Grignard reagent with the α-haloalkanoic acid ester of general formula (III) being carried out in the presence of a nickel compound.
