Preyssler catalyst, [NaP5W30O110]14−: A green, efficient and reusable catalyst for esterification of salicylic acid with aliphatic and benzylic alcohols

A series of eco-friendly solid acid catalysts, including H14[NaP5W30O110], H14–P5, H14[NaP5W29MoO110], H14–P5Mo, and silica supported H14[NaP5W30O110], H14–P5/SiO2 have been used as catalysts for esterification of salicylic acid with aliphatic alcohols (methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, t-butanol, 1-pentanol, and 2-pentanol) and benzylic alcohols (benzyl, 2-methylbenzyl, 2-chlorobenzyl, 4-bromobenzyl, 3-nitrobenzyl, and 4-methoxy benzyl) alcohol.The performance of different forms of Preyssler's anion in the presence of dichloroethan as the solvent of choice was compared with H2SO4. In all cases, maximum of ester yields and product selectivity (100%) was observed by using H14–P5 as catalyst. The esterification reactions were extended with other aliphatic and aromatic acids.