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2-Alkylidene-4-oxothiazolidine S-oxides: synthesis and stereochemistry
(Oxford : Pergamon-Elsevier Science Ltd, 2013)
A series of 5-unsubstituted and 5-substituted 2-alkylidene-4-oxothiazolidine-S-oxides were synthesized by the sulfur-oxidation with m-CPBA. The stereochemistry of 5-substituted sulfoxides was determined by means of NMR ...
Unusual mode of reactivity of 2-alkylidene-4-oxothiazolidine S-oxides under the Pummerer reaction conditions
(Oxford : Pergamon-Elsevier Science Ltd, 2013)
The reactivity of 2-alkylidene-4-oxothiazolidine S-oxides under the Pummerer reaction conditions, using Ac2O, TFAA, SOCl2 and SOBr2 as initiators, has been examined. Almost all reactions proceeded with absolute regioselectivity ...
Catalytic oxidations of enolizable ketones using 2-alkylidene-4- oxothiazolidine vinyl bromide
(Oxford : Pergamon-Elsevier Science Ltd, 2011)
Direct oxidation of enolizable ketones to α-hydroxy derivatives, vicinal dicarbonyls or tricarbonyl compounds has been achieved by a catalytic amount of 2-alkylidene-4-oxothiazolidine vinyl bromide in DMSO as a solvent. ...
Structure, configuration, conformation and quantification of the push pull-effect of 2-alkylidene-4-thiazolidinones and 2-alkylidene-4,5-fused bicyclic thiazolidine derivatives
(Oxford : Pergamon-Elsevier Science Ltd, 2010)
Structures of a series of push-pull 2-alkylidene-4-thiazolidinones and 2-alkylidene-4,5-fused bicyclic thiazolidine derivatives were optimized at the B3LYP/6-31G(d) level of theory in the gas phase and discussed with respect ...
The effect of steric repulsion on the torsional potential of n-butane: a theoretical study
(Oxford : Pergamon-Elsevier Science Ltd, 2015)
The origin of the rotational barriers in n-butane and gauche conformational energy, the prototypes of steric repulsion, has been re-examined by using energy decomposition analysis. The Pauli repulsion was found to be an ...
A novel procedure for the aromatization of ring a in 19-nortestosterone
(Elsevier, 1977)
A convenient, 40% overall yield synthesis of 2,3,17β-triacetoxy-1,3,5(10)-estratriene is described, which involves epoxidation of 19-nortestosterone and subsequent acetylation, lead tetra-acetate acetoxylation of the ...
pi-Annulation reactions of 4-thiazolidinone enaminones in the synthesis of fused bi- and tri-cyclic compounds
(Oxford : Pergamon-Elsevier Science Ltd, 2012)
The a-C position in 4-oxo thiazolidinones functions as one of the three possible nucleophilic sites in these molecules. We used the inherent reactivity of alpha-C of the exocyclic double bond (a so called push pull system) ...
endo-Mode cyclizations of vinylogous N-acyliminium ions as a route to the synthesis of condensed thiazolidines
(Oxford : Pergamon-Elsevier Science Ltd, 2011)
endo-Mode cyclizations of vinylogous N-acyliminium ions incorporating heteroatom-based nucleophiles have been examined as a route to the synthesis of condensed thiazolidines. The scope of these reactions and stereochemical ...
The reaction of lead tetra-acetate with some unbranched α,ω-diols
(Elsevier, 1969)
Unbranched α,ω-diols are mainly converted by means of lead tetra-acetate in refluxing benzene to the corresponding ethers of di-α-tetrahydrofuryl, di-α-tetrahydropyryl and/or α-tetrahydrofuryl-α′-tetrahydropyryl type. Thus, ...
Studies of the regioselective ring-opening closing mode of functionally different thiazolidine type enaminones: en route to the synthesis of trithiaazapentalene derivatives
(Oxford : Pergamon-Elsevier Science Ltd, 2013)
Trithiaazapentalene derivatives were prepared by the reaction of 2-alkylidene-4-oxothiazolidines with Lawesson's reagent. They are classified as two structurally different trithiaazapentalene compounds that have different ...