92585-24-5Relevant articles and documents
Asymmetric Synthesis of Deoxypropionate Derivatives via Catalytic Hydrogenolysis of Enantioenriched Z-Ketene Heterodimers
Chen, Shi,Ibrahim, Ahmad A.,Mondal, Mukulesh,Magee, Anthony J.,Cruz, Adam J.,Wheeler, Kraig A.,Kerrigan, Nessan J.
, p. 3248 - 3251 (2015)
A diastereoselective approach to deoxypropionate derivatives through Pd/C-catalyzed hydrogenolysis of enantioenriched ketene heterodimers is described. Catalytic hydrogenolysis of the Z-isomer of ketene heterodimers facilitates access to anti-deoxypropion
Catalytic Asymmetric Synthesis of Ketene Heterodimer β-Lactones: Scope and Limitations
Chen, Shi,Ibrahim, Ahmad A.,Peraino, Nicholas J.,Nalla, Divya,Mondal, Mukulesh,Van Raaphorst, Maxwell,Kerrigan, Nessan J.
, p. 7824 - 7837 (2016/10/03)
In this article we describe extensive studies of the catalytic asymmetric heterodimerization of ketenes to give ketene heterodimer β-lactones. The optimal catalytic system was determined to be a cinchona alkaloid derivative (TMS-quinine or Me-quinidine). The desired ketene heterodimer β-lactones were obtained in good to excellent yields (up to 90%), with excellent levels of enantioselectivity (≥90% ee for 33 Z and E isomer examples), good to excellent (Z)-olefin isomer selectivity (≥90:10 for 20 examples), and excellent regioselectivity (only one regioisomer formed). Full details of catalyst development studies, catalyst loading investigations, substrate scope exploration, protocol innovations (including double in situ ketene generation for 7 examples), and an application to a cinnabaramide A intermediate are described. The addition of lithium perchlorate (1-2 equiv) as an additive to the alkaloid catalyst system was found to favor formation of the E isomer of the ketene heterodimer. Ten examples were formed with moderate to excellent (E)-olefin isomer selectivity (74:25 to 97:3) and with excellent enantioselectivity (84-98% ee).
Chirality and fragrance chemistry: Stereoisomers of the commercial chiral odorants muguesia and pamplefleur
Abate, Agnese,Brenna, Elisabetta,Fuganti, Claudio,Gatti, Francesco G.,Giovenzana, Tommaso,Malpezzi, Luciana,Serra, Stefano
, p. 1281 - 1290 (2007/10/03)
(Chemical Equation Presented) The work describes the enzyme-mediated preparation and the odor evaluation of the single stereoisomers of the commercial odorants Muguesia and Pamplefleur. The synthetic approach to Muguesia stereoisomers helped to clear the assignment of the relative configuration of intermediate diols 5. The odor response of Pamplefleur isomers was found to be rather unusual. No stereoisomer prevailed, but each one played a definite role in establishing the odor sensation of the final blend.