2957-06-4Relevant articles and documents
SILYL NITRONATES, NITRILE OXIDES, AND DERIVED 2-ISOXAZOLINES IN ORGANIC SYNTHESIS. FUNCTIONALIZATION OF BUTADIENE, A NOVEL ROUTE TO FURANS AND 2-ISOXAZOLINES AS AN ALTERNATIVE TO ALDOL-TYPE CONDENSATIONS
Das, Nalin B.,Torssell, Kurt B. G.
, p. 2247 - 2254 (1983)
Mono- and di-addition of silylnitronates and nitrile oxides is a useful procedure for functionalizing butadiene leading to cyano and acyl derivatives.A novel route to 2,5-disubstituted furans is also established.The potential of the method in carbohydrate synthesis is pointed out.The route via 2-isoxazoline is shown to be a useful alternative to aldol-type reactions in organic synthesis. 15a has been studied by X-ray diffraction and shown to be meso form.
The cinchona primary amine-catalyzed asymmetric epoxidation and hydroperoxidation of α,β-unsaturated carbonyl compounds with hydrogen peroxide
Lifchits, Olga,Mahlau, Manuel,Reisinger, Corinna M.,Lee, Anna,Fares, Christophe,Polyak, Iakov,Gopakumar, Gopinadhanpillai,Thiel, Walter,List, Benjamin
supporting information, p. 6677 - 6693 (2013/06/05)
Using cinchona alkaloid-derived primary amines as catalysts and aqueous hydrogen peroxide as the oxidant, we have developed highly enantioselective Weitz-Scheffer-type epoxidation and hydroperoxidation reactions of α,β-unsaturated carbonyl compounds (up to 99.5:0.5 er). In this article, we present our full studies on this family of reactions, employing acyclic enones, 5-15-membered cyclic enones, and α-branched enals as substrates. In addition to an expanded scope, synthetic applications of the products are presented. We also report detailed mechanistic investigations of the catalytic intermediates, structure-activity relationships of the cinchona amine catalyst, and rationalization of the absolute stereoselectivity by NMR spectroscopic studies and DFT calculations.
