Acylation and Related Reactions

Acylation. A/-Acylation and related reactions ate brought about in straightforward ways with acyl chloride or acid anhydride, although the proximity of the carboxyl group may produce other reactions, eg, oxa2olinone formation, under some conditions. 

Classically, vinylsilanes have served as nucleophiles in Friedel-Crafts acylation and related reactions with strong electrophiles.4,4a 89 These strategies have been employed in the synthesis of natural products.90,9011... 

Marquie, J. and Salmoria, G. and Poux, M. and Laporterie, A. and Dubac, J. and Roques, N. (2001). Acylation and Related Reactions under Microwaves. 5. Development to Large Laboratory Scale with a Continuous-Flow Process. Ind. Eng. Chem. Res., 40, 4485-4490. 

Dimethylaminopyridine (DMAP) is very much more effective than pyridine in catalyzing acylation and related reactions (78AG602), and in this case many of the highly reactive intermediates can be isolated. 

Pyridine is widely used as a reaction medium in acylation and related reactions involving, for example, acyl chlorides, anhydrides, sulfonyl chlorides, or chlorosilanes, and has the particular advantage that it can function both as a catalyst and acid acceptor. It is usually the solvent of choice for the trimethylsilylation of alditols and sugars,292-298 and for various derivatization reactions such as tritylation and sulfonylation.299-307 The tritylation reaction has been reviewed.306... 

Kozhevnikov, I. V. Friedel-Crafts acylation and related reactions catalyzed by heteropoly acids. Appl. Cat. A 2003, 256, 3-18. 

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