83466-88-0Relevant academic research and scientific papers
Unique Template Effects of Distannoxane Catalysts in Transesterification of Diol esters
Otera, Junzo,Dan-oh, Nobuhisa,Nozaki, Hitosi
, p. 3065 - 3074 (2007/10/02)
1,n-Diol diacetates (n = 2,3,4) are selectively converted into the corresponding monoacetates by distannoxane-catalyzed transesterification.Such unique selectivity is not encountered with 1,n-diol diacetates where n>/=5.A great difference in reactivity is also seen in the transesterification between methyl butyrate and 1,n-diol monoacetates: the ethylene glycol derivative sluggishly undergoes transesterification whereas higher homologs react smoothly.The unique template effects of the catalysts are discussed in terms of cooperation of two different tin atoms which are located in the proximity.
Highly Selective Monoacylation of Symmetric Diols Catalyzed by Metal Sulfates Supported on Silica Gel
Nishiguchi, Takeshi,Kawamine, Katsumi,Ohtsuka, Tomoko
, p. 312 - 316 (2007/10/02)
Several 1,α-diols, ranging from 1,2-ethanediol to 1,16-hexadecanediol, were monoacylated with high selectivity by reaction with esters in the presence of metal sulfates or hydrogen sulfates, like Ce(SO4)2 and NaHSO4, supported on silica gel.Symmetrical secondary diols were also selectively monoformylated, by reaction with ethyl formate.This method of selective esterification is simple and practical.The yield of monoester depends upon both the composition and the volume of the solvent (an ester/alkane mixture).Unsupported NaHSO4 also catalyzed monoacylation, but the selectivity was less than in monoacylations catalyzed by the supported reagent.The selectivity can be explained by the following reasons: (1) monoacylated products are formed selectively because the diol, but not the monoester, is preferentially adsorbed on the surface of the catalysts, where esterification then occurs, and (2) thin diol layers are formed on the surface of the catalysts due to limited solubility of the diols in the solvent.
