Acylation of Alcohols, Part 1: with Acyl Halides скачать в хорошем качестве

Acylation of Alcohols, Part 1: with Acyl Halides

In this video we’ll first have a short review of the use and industrial manufacturing strategies of carboxylic esters. Then I’ll show you some examples of the use of acyl halides, mostly acyl chlorides, as electrophiles for preparing esters, and of potential side reactions. Acyl halides react with alcohols both under acidic or basic conditions. In the absence of bases the reaction mixture will turn strongly acidic, and a number of side reactions can occur, such as the conversion of the starting alcohols into alkyl halides, ethers or olefins. These side reactions can be prevented by weak bases, such as pyridine or DMF. Bases can, however, also bring about the formation of ketenes from the starting acyl halide and thereby of a new set of byproducts. Further examples: Org. Lett. 2017, 19, 3099-3102 (monoacylation of carbohydrates); Syn. Comm. 2012, 42, 921-931 (PTC); Adv. Syn. Catal. 2006, 348, 2057-2062 (in water); J. Org. Chem. 1990, 55, 4448-4454 (ArC(CF3)2OH); J. Am. Chem. Soc. 1958, 80, 1944-1946 (ArOH); Org. Syn. 2000, 77, 162 (lutidine); 1999, 76, 275 (pyridine); 1971, 51, 11 (pyridine).