82794-36-3Relevant articles and documents
Multicomponent, Enantioselective Michael-Michael-Aldol-β-Lactonizations Delivering Complex β-Lactones
Van, Khoi N.,Romo, Daniel
, p. 632 - 643 (2018/01/27)
Optically active, tertiary amine Lewis bases react with unsaturated acid chlorides to deliver chiral, α,β-unsaturated acylammonium salts. These intermediates participate in a catalytic, enantioselective, three-component process delivering bi- and tricyclic β-lactones through a Michael-Michael-aldol-β-lactonization. In a single operation, the described multicomponent, organocascade process forms complex bi- and tricyclic β-lactones by generating four new bonds, two rings, and up to four contiguous stereocenters. In the racemic series, yields of 22-75% were achieved using 4-pyrrolidinopyridine as Lewis base. In the enantioselective series employing isothiourea catalysts, a kinetic resolution of the initially formed racemic Michael adduct appears operative, providing yields of 46% to quantitative (based on 50% max) with up to 94:6 er. Some evidence for a dynamic kinetic asymmetric transformation for tricyclic-β-lactone 1d was obtained following optimization (yields up to 61%, 94:6 er) through a presumed reversible Michael.
2 - methyl malonic acid diester synthetic method of the compound
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Paragraph 0054-0056, (2017/08/10)
The invention discloses a synthetic method of 2-diester methylmalonate compounds, and relates to the technical field of carboxylic ester preparation. The synthetic method comprises steps as follows: C, sulfonic acid 2-ethyl N-cyanoethanimideate IV and cyanide react under the action of a solvent and a catalyst, and 2-methyl malononitrile V is obtained; D, 2-methyl malononitrile V and ROH react under the action of the solvent and concentrated sulfuric acid, and products of 2-diester methylmalonate compounds I are obtained, wherein MCN is cyanide, M is Na or K, ROH is alkyl alcohol, alkenyl alcohol or a fluoride group containing alcohol, is benzyl alcohol or benzyl alkyl, halogen or nitro substituted benzyl alcohol, or is phenol or C1-C5 containing alkyl, halogen or nitro substituted phenol. The method is unique, the reaction conditions are mild, the reaction process is basically free of by-products, the yield is high, adopted raw materials have extensive sources, and acetaldehyde can be used as the raw material; the synthetic method is applicable to industrial production.
Air- and water-tolerant rare earth guanidinium BINOLate complexes as practical precatalysts in multifunctional asymmetric catalysis
Robinson, Jerome R.,Fan, Xinyuan,Yadav, Jagjit,Carroll, Patrick J.,Wooten, Alfred J.,Pericàs, Miquel A.,Schelter, Eric J.,Walsh, Patrick J.
supporting information, p. 8034 - 8041 (2014/06/23)
Shibasaki's REMB catalysts (REMB; RE = Sc, Y, La-Lu; M = Li, Na, K; B = 1,1′-bi-2-naphtholate; RE/M/B = 1/3/3) are among the most enantioselective asymmetric catalysts across a broad range of mechanistically diverse reactions. However, their widespread us
