59438-62-9Relevant articles and documents
Photocatalyzed Generation of Nitrosocarbonyl Intermediates Under Solar Light Irradiation
Basile, Teresa,Capaldo, Luca,Ravelli, Davide,Quadrelli, Paolo
, p. 1443 - 1447 (2019/06/08)
Tetrabutylammonium decatungstate (TBADT) has emerged as a valuable photocatalyst for sunlight-induced organic reactions. In this communication we wish to present its use for the photocatalytic oxidation of hydroxamic acids to generate fleeting nitrosocarb
Hetero Diels–Alder Reaction and Ene Reaction of Acylnitroso Species in situ Generated by Hypoiodite Catalysis
Uraoka, Saki,Shinohara, Ikumi,Shimizu, Hisato,Noguchi, Keiichi,Yoshimura, Akira,Zhdankin, Viktor V.,Saito, Akio
supporting information, p. 6199 - 6203 (2018/11/10)
As a first non-metal-catalyzed oxidation for the in situ generation of acylnitroso species, we describe the hypoiodite catalysis using tetra-n-butylammonium iodide as precatalyst with tert-butyl hydroperoxide or hydrogen peroxide as a terminal oxidant. Th
Probing competitive and co-operative hydroxyl and ammonium hydrogen-bonding directed epoxidations
Brambilla, Marta,Brennan, Méabh B.,Csatayová, Kristína,Davies, Stephen G.,Fletcher, Ai M.,Kennett, Alice M.R.,Lee, James A.,Roberts, Paul M.,Russell, Angela J.,Thomson, James E.
, p. 10297 - 10309 (2018/05/31)
The diastereoselectivities and rates of epoxidation (upon treatment with Cl3CCO2H then m-CPBA) of a range of cis- and trans-4- aminocycloalk-2-en-1-ol derivatives (containing five-, six-, and seven-membered rings) have been investigated. In all cases where the two potential directing groups can promote epoxidation on opposite faces of the ring scaffold, evidence of competitive epoxidation pathways, promoted by hydrogen-bonding to either the in situ formed ammonium moiety or the hydroxyl group, was observed. In contrast to the relative directing group abilities already established for the sixmembered ring system (NHBn ? OH > NBn2), an N,N-dibenzylammonium moiety appeared more proficient than a hydroxyl group at directing the stereochemical course of the epoxidation reaction in a five- or seven-membered system. In the former case, this was rationalized by the drive to minimize torsional strain in the transition state being coupled with assistance from hydrogenbonding to the ammonium moiety. In the latter case, this was ascribed to the steric bulk of the ammonium moiety disfavoring conformations in which hydrogen-bonding to the hydroxyl group results in direction of the epoxidation to the syn face. In cases where the two potential directing groups can promote epoxidation on the same face of the ring scaffold, an enhancement of epoxidation diastereoselectivity was not observed, while introduction of a second, allylic heteroatom to the substrate results in diminishment of the rate of epoxidation in all cases. Presumably, reduction of the nucleophilicity of the olefin by the second, inductively electron-withdrawing heteroatom is the dominant factor, and any assistance to the epoxidation reaction by the potential to form hydrogen-bonds to two directing groups rather than one is clearly unable to overwhelm it.
