Isosorbide dilaurate

Sorbitol. Sorbitol is the sugar alcohol obtained by reduction of glucose and it can be dehydrated to either isosorbide or to 1,4- and 2,5-sorbitan in acid or base catalyzed processes, respectively. Using sulfonic acid functionalized MCM-41 type materials lauric acid esters of isosorbide can be achieved quite selectively starting from sorbitol (>95% selectivity towards isosorbide dilaurate at 33% lauric acid conversion) in a dehydration-esterification... 

Mesoporous sulfonie acids are of particular interest for reactions involving molecules that are too large to access the smaller pores of conventional molecular sieves or for the preparation of bulky reaction products. In the hydroxyalkylation of methylfuran with acetone, the ordered mesoporous sulfonic acids surpass large pore zeolites such as H-Beta, with an excellent yield of 82 % for 2,2-bis(5-methyl-furyljpropane instead of 45 % for H-Beta [30]. The activity of the sulfonic MCMs is also clearly superior to that of zeolites Beta and Y in the o-sorbitol dehydration-esterification forming isosorbide dilaurate, or in the liquid biphasic preparation of monoesters starting from various polyols and fatty acids [30]. The catalyst of Stein and co-workers was highly active and selective in the tetrahydropyranylation of ethanol with 2,3-dihydropyran [31]. In this type of reaction also the non-modified H-MCM-41 material is an excellent catalyst [40]. 

We have prepared and characterized three linear isosorbide containing polyurethanes with toluene diisocyanate (TDI), 4,4 -diphenylmethane diisocyanate (MDI), and 1,6-hexamethylene diisocyanate (HMDI) P(I-TDI), P(I-MDI), and P(I-HMDI). These polyurethanes have been synthesized as described in the experimental section by solution polymerization of isosorbide with the corresponding diisocyanate in dimethylacetamide using dibutyl-tin dilaurate as the catalyst at 75 C for 24 hours. All polymers have been isolated in quantitative yield by precipitation in methanol or water (5). 

We have prepared two linear soluble polyurethanes P(LAGA-MDI) and P(LAGA-HMDI) by solution polymerization of LAGA with MDI and HMDI respectively in dimethyiacet-amide as a solvent using dibutyltin dilaurate as a catalyst at 75°C over 24 hours According to the procedure used in the preparation of the isosorbide polyurethanes as described in the experimental section. Both polymers have been isolated in quantitative yield in their lactone form by precipitation from chloroform (15). 

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