1177-36-2

Upstream product

• 1119-87-5 dodecane-1,2-diol 
• 98-88-4 benzoyl chloride 
• 1188-81-4 1,2-O-diacetyl dodecanediol-1,2 

Relevant academic research and scientific papers

Lipase-catalyzed stereoresolution of long-chain 1,2-alkanediols: A screening of preferable reaction conditions

Scalable lipase-catalytic method for the kinetic resolution of long-chain 1,2-alkanediol enantiomers via stereoselective cleavage of esters was developed. The influence of lipase, reaction medium, nucleophile, temperature and the structure of the acyl group on the reaction velocity, the stereopreference and the stereoselectivity of the deacylation was studied. In addition, the rate of the spontaneous intramolecular migration of different acyl groups was determined for the intermediate 2-monoesters. The acyl group migration may diminish the apparent stereoselectivity of the two-step process if fast migrating acyl groups are used. It was found that the migration rate of different acyl groups differs by up to two orders of magnitude, being faster for acetyl and isobutyryl and much slower for butyryl and benzoyl groups. The best results were obtained by the sequential methanolysis of bis-butyryl-1,2-alkanediols in an acetonitrile/methanol mixture catalyzed by Candida antarctica lipase B (CALB) at 20 °C, affording (S)-1,2-alkanediols. Stereo- and chemoselective crystallization of the deacylated (S)-1,2-alkanediols from the reaction mixture complements the enzymatic process improving the stereochemical purity to up to ee > 99.8%. (R)-1,2-Alkanediol 2-monoesters were separated from the mother liquor and enriched stereochemically by repeated incubation with CALB, then separated, hydrolyzed with alkali and crystallized to afford (R)-alkanediols of ee > 99.8%.

Organotin-Mediated Monoacylation of Diols with Reversed Chemoselectivity: A Convenient Synthetic Method

The organotin-mediated monoesterification of unsymmetrical diols with reversed chemoselectivity has been explored to ascertain scope and limits of the method and to provide an easy and convenient synthetic procedure.The reaction has been performed on a set of substituted diols with some acylating agents usually employed as protecting groups.Two different procedures have been devised to obtain either the desired diol monoesters directly or the corresponding trialkylsilyl ethers as protected derivatives.The latter provides a convenient approach to the preparation of easily interconvertible diol monoesters.Also, the reaction has been optimized as a one-pot procedure, avoiding the isolation and purification of the stannylated intermediates.The reversed monoesterification method has been successfully applied to 1,2-, 1,3-, and 1,4-diols of primary-secondary, primary-tertiary, and secondary-tertiary types and to ether functions containing 1,2-diols.Within its limits, the described method represents the first direct one-pot monoesterification of diols at the most substituted site, allowing some remarkable achievements as (a) an almost regiospecific reversed monobenzoylation of some 1,2-diols, (b) the selective acylation of the tertiary hydroxyl of a primary-tertiary diol, and (c) a highly selective preparation of secondary pivalate of primary-secondary diols.