22440-35-3Relevant articles and documents
Synthesis of Epoxides from Alkyl Bromides and Alcohols with in Situ Generation of Dimethyl Sulfonium Ylide in DMSO Oxidations
Zhang, Zhi-Wei,Li, Hai-Bo,Li, Jin,Wang, Cui-Cui,Feng, Juan,Yang, Yi-Hua,Liu, Shouxin
, p. 537 - 547 (2020/01/02)
Direct conversion of the readily available alkyl bromides and alcohols to value-added epoxides using dimethyl sulfoxide (DMSO) under mild reaction conditions has been developed. Benzyl and allyl bromides, and activated and unactivated alcohols all proceeded smoothly to give epoxides in high to excellent yield. Dimethyl sulfide, generated by DMSO oxidations, was in situ elaborated to form the substituted dimethyl sulfonium ylide species that participates in the Corey-Chaykovsky epoxidation in a domino and one-pot fashion, respectively.
Chiral Macrocyclic Organocatalysts for Kinetic Resolution of Disubstituted Epoxides with Carbon Dioxide
Ema, Tadashi,Yokoyama, Maki,Watanabe, Sagiri,Sasaki, Sota,Ota, Hiromi,Takaishi, Kazuto
supporting information, p. 4070 - 4073 (2017/08/15)
Among chiral macrocycles 1 synthesized, 1m with the 3,5-bis(trifluoromethyl)phenylethynyl group was the best organocatalyst for the enantioselective synthesis of cyclic carbonates from disubstituted or monosubstituted epoxides and CO2. The X-ray crystal structure of 1m revealed a well-defined chiral cavity with multiple hydrogen-bonding sites that is suitable for the enantioselective activation of epoxides. A catalytic cycle proposed was supported by DFT calculations.
Catalytic, regioselective, and green methods for rearrangement of 1,2-diaryl epoxides to carbonyl compounds employing metallic triflates, Br?nsted-acidic ionic liquids (ILs), and IL/microwave; Experimental and computational substituent effect study on aryl versus hydrogen migration
Jamalian, Arezu,Rathman, Benjamin,Borosky, Gabriela L.,Laali, Kenneth K.
, p. 1 - 11 (2014/11/08)
The Lewis-acid catalyzed rearrangement of parent trans-stilbene oxide 1 was studied with M(OTf)3/DCM and M(OTf)3/[BMIM][BF 4] (M = Bi, Al, Ga, Sc, and Yb; [BMIM] = butylmethylimidazolium) and Zn(NTf2)2, and with Bi(OTf)3/[BMIM][X] (X = NTf2, OTf, PF6, and BF4), employing 5 mol% of catalyst. Selective formation of 2,2-dipheylacetaldehyde 2 (phenyl migration product) was observed in all cases, with Bi(OTf)3 proving most efficient. The rearrangement of 1 was also effected in [BMIM][X] (X = NTf 2, OTf, PF6, and BF4) without an added catalyst under microwave MW irradiation, and X = PF6 gave the highest yield and selectivity. Efficient and selective rearrangement of 1-2 was also observed with 0.1-0.3 equiv. of [BMIM(SO3H)][OTf] in DCM and in [BMIM][X]. A substituent effect study was performed with a series of singly substituted 1,2-diphenyl oxiranes (with X = OMe, Me, F, CN, and NO2) with 5 mol% Bi(OTf)3 in DCM and in [BMIM][NTf2]. Notable formation of ketones was observed with the NO2 and CN derivatives. Competing formation of ketones was also observed in [BMIM][PF6] under MW and under Br?nsted acid catalysis with [BMIM(SO3H)][OTf] in DCM and in [BMIM][NTf2]. The aryl versus H migration was studied computationally by DFT and MP2 methods and by including solvation effects (IEFPCM).
