111221-79-5Relevant articles and documents
An NMR and MD modeling insight into nucleation of 1,2-alkanediols: Selective crystallization of lipase-catalytically resolved enantiomers from the reaction mixtures
Parve, Omar,Reile, Indrek,Parve, Jaan,Kasvandik, Sergo,Kudrjasova, Marina,Tamp, Sven,Metsala, Andrus,Villo, Ly,Pehk, Tonis,Jarvet, Jueri,Vares, Lauri
, p. 12795 - 12801 (2013)
The work on developing a scalable lipase-catalytic method for the kinetic resolution of long-chain 1,2-alkanediols, complemented by crystallization of the pure enantiomers from the reaction mixtures, offered the possibility of a more detailed study of the aggregation of such diols. MD modeling, mass spectrometry, 1H NMR, and DOSY studies provided a novel insight into the nucleation process. An efficient protocol for stereo- and chemoselective crystallization of (S)-1,2-dodecanediol and related compounds from the crude bioconversion mixtures was developed.
Lipase-catalyzed stereoresolution of long-chain 1,2-alkanediols: A screening of preferable reaction conditions
Parve, Jaan,Reile, Indrek,Aid, Tiina,Kudrja?ova, Marina,Müürisepp, Aleksander-Mati,Vallikivi, Imre,Villo, Ly,Aav, Riina,Pehk, T?nis,Vares, Lauri,Parve, Omar
, p. 60 - 69 (2015/04/14)
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%.
A Systematic Study on the Bakers'Yeast Reduction of 2-Oxoalkyl Benzoates and 1-Chloro-2-alkanones
Sakai, Takashi,Wada, Kou,Murakami, Takahiko,Kohra, Kiichiro,Imajo, Norihisa,et al.
, p. 631 - 638 (2007/10/02)
The bakers' yeast reduction of a series of 2-oxoalkyl arenecarboxylates (1a-f) (R=CH3 to n-C6H13; X=H) and the phenyl-modified derivatives (1g-l) (R=n-C5H11, X=OH, CH3, F, Cl, Br, or I) as well as 1-chloro-2-alkanones R(C=O)CH2Cl (6a-f) (R=CH3 to n-C6H13) were systematically investigated.The substrate specificities, configuration and percentee of the reduction products were found to be highly dependent on the length of the alkyl group (R) and the α substituent.Thus, the benzoates 1a-f gave optically active 2-hydroxyalkyl benzoates (2a-f) (R, configuration, percentee) (a: CH3, S, 99; b: C2H5, S, 98; c: C3H7, S, 26; d: n-C4H9, R, 55; e: n-C5H11, S, 15; f: n-C6H13, S, 63) in 11-91percent yields.Among the modification experiments of the phenyl group, 1g-l, the p-iodo substituent markedly increased the ee from 15 to 71percent, although the yield was rather lowered (22percent yield).The reduction of α-chloro ketones 6a-f also gave optically active 1-chloro-2-alkanols (7a-f) in 16-69percent yields.
