Octanoyl chloride, acylations using

A recent article reported the use of strongly acidic mesoporous aluminosilicates prepared from zeolite seeds in the acylation of anisole with octanoyl chloride.[30] The mesoporosity improving the transport of the reactants and the presence of strong acid sites lead to high conversion (>90 %) and high selectivity (100 %). 

Tridimensional Y and BEA zeolites are also utilized as efficient catalysts in the acylation of tetralin with acyl chlorides. By using octanoyl chloride and butyroyl chloride in the presence of zeolite Y(40), good yields in the acylation products are achieved (83% and 77% yield, respectively, after 8 h), whereas acetyl chloride (AC) leads only to less than 20% yield of the two isomeric ketones 1 and 2 (1/2 = 7.5) (Scheme 4.2). This trend is correlated to the influence of the chain length of the acylating agent on the efficiency of Friedel-Crafts acylation over zeolite catalysts previously discovered and rationalized. The lower activity of zeolite Y(40) with AC is related to the strong adsorption of organic species, either acetic acid (AAC) or acetyl tetralin. 

The mesoporous aluminosilicate AlMCM-41-type material, prepared from BEA zeolite seeds, can be utilized as catalyst in the acylation of anisole with acyl chloride with the aim of improving the transport of the reactants, especially for the relatively hindered molecules such as octanoyl chloride. The catalyst shows good activity, being para-octanoyl anisole obtained in 90% yield after 1 h. As commonly observed, the use of carboxylic acid as acylating agent results in a slower process (-20% yield after 26 h) due to its lower electrophilicity and the production of water that inhibits the active sites of the zeolite, as previously observed by Beers et al. ... 

Conventional synthesis of such materials employs fiitty-acid chlorides or anhydrides in organic solvents. Recently, a fiee-solvent method to esterify starch was developed in our laboratory using formic acid and octanoyl chloride as the gelatinizing and acylating agents respectively. After optimization of reaction conditions, starch octanoate with DS of 1.7 was obtained with a recuperation yield of 89 %. ... 

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