616-51-3Relevant articles and documents
Asymmetric transesterification of secondary alcohols catalyzed by feruloyl esterase from Humicola insolens
Hatzakis, Nikos S.,Smonou, Ioulia
, p. 325 - 337 (2007/10/03)
A new asymmetric transesterification of secondary alcohols catalyzed by feruloyl esterase from Humicola insolens has been found. Although alcohols are not the natural substrates for this enzyme, a high R enantioselectivity was observed. Stereochemical studies showed that variations in substrate structure lead to strong variations in enantioselectivity. The highest enantioselectivities are obtained when the β-carbon of the secondary alcohol is tertiary or quaternary.
The Influence of Steric Effects on the Selectivity of Radical CC Bond Formation Reactions
Giese, Bernd,Harnisch, Hanna,Luening, Ulrich
, p. 1345 - 1351 (2007/10/02)
Bulky substituents R1 and R2 at radical 5 decrease the rate of addition to diethyl fumarate to a larger extent than to methyl acrylate (Table 1).The comparison with H-abstraction, which is only slightly influenced by steric effects, shows that 5e (R2 = t-C4H9) reacts at least 235 times slower with diethyl fumarate than 5a (R2 = CH3) (Table 2).Therefore, the stereoselectivity of cyclic radicals 1 (n = 1,2) increases if the CC bond formation reaction is carried out with diethyl fumarate instead of methyl acrylate.
RATIO OF POLAR AND RADICAL PROCESSES IN THERMAL TRANSFORMATIONS OF PEROXIDES. I. EFFECT OF THE LENGTH AND BRANCHING OF THE CHAIN IN THE ALKYL SUBSTITUENT AT THE α-CARBON ATOM OF THE ACYL GROUP
Stankevich, A. I.,Zyat'kov, I. P.,Lazareva, A. M.,El'nitskii, A. P.
, p. 1543 - 1548 (2007/10/02)
Acetyl 2-methylpropionyl, acetyl 2-methylbutyryl, acetyl 2-methyloctanoyl, acetyl 2,3-dimethylbutyryl, and acetyl 2,3,3-trimethylbutyryl peroxides are transformed thermally under the investigated experimental conditions with the formation of the corresponding acyl alkyl carbonates and radical products.The ratio of the polar and radical processes is affected by the length and branching of the chain in the hydrocarbon substituent at the α-carbon atom of the acyl group.
