Rhodium-catalyzed synthesis of unsymmetrical di(aryl/heteroaryl)methanes using aryl/heteroarylmethyl ketones via CO–C bond cleavage
作者:Guangzhe Li、Mieko Arisawa、Masahiko Yamaguchi
DOI:10.1039/c4cc00816b
日期:——
RhH(PPh3)4 and 1,2-bis(diphenylphosphino)benzene catalyze the reaction of aryl/heteroarylmethyl ketones and arylheteroaryl ethers giving unsymmetrical diarylmethanes containing one or two heteroarenes in high yields. The reaction does not use alkali metal bases, and therefore does not form large amounts of metal waste.
Thieme Chemistry Journals Awardees – Where Are They Now? Rhodium-Catalyzed Synthesis of Unsymmetric Di(heteroaryl) Ethers Using Heteroaryl Exchange Reaction
di(heteroaryl) ethers were synthesized by the rhodium-catalyzed heteroaryl exchangereaction of heteroaryl aryl ethers and heteroaryl esters at equilibrium. Diverse unsymmetric di(heteroaryl) ethers containing five- and six-membered heteroarenes were obtained. Di(heteroaryl) ethers can be synthesized starting from diaryl ethers, because heteroaryl aryl ethers are obtained by the heteroaryl exchange reaction
ureas, and cyclic imides using heteroaryl aryl ethers. The reaction involves the covalent bond-exchange reaction of N–CO and HetAr–O bonds without using metal bases and exhibits a broad applicability, giving diverse C–N-linked bi(heteroaryl)s containingfive- and six-membered heteroarenes. The N-heteroarylation of N–H azoles/azolones and pyridone proceeds at higher reaction temperatures.
Cycloalkyl heteroaryl sulfides are efficiently synthesized by the single -bond cleavage and exchange reaction of S-cycloalkyl thioesters and heteroaryl ethers without using a base. The method is applicable to steroids at the A- and D -rings, and provides diverse heteroarylthiolated steroids with five- and six -membered heteroarenes.