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Intramolecular cyclization of 3β-acetoxy-16-picolinylidene-5-androsten-17-one by catalytic hydrogenation
(Elsevier, 1970)
Intramolecular cyclization by catalytic hydrogenation of 3β-acetoxy-16-picolinylidene-5-androsten-17-one (IV) (80° and 50-60 atm of hydrogen pressure over Pd/C as catalyst) gives rise to the formation of two cyclic products, ...
Acid-catalyzed rearrangement of some steroidal isoxazolidines
(Elsevier, 1999)
Acid-catalyzed reaction of the steroidal Δ 1 -unsaturated 3β,5β- epoxyimino compound 2 and Δ 3 -unsaturated 1β,5β-epoxyimino products 3 and 7, results in intramolecular rearrangement involving the N-CH 3 group to give the ...
The conformational equilibrium of 1,3-dichloro-5-methylcyclohexane
(Elsevier, 1981)
Two of the stereoisomers of the title compound were prepared and their dipole moments were measured. For the r-1,c-3-dichloro-t-5-methylcyclohexane, the free energy difference between conformers with axial-axial (aa) and ...
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 ...
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 ...
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 ...
Reactions with lead tetraacetate-I. Oxidation of saturated aliphatic alcohols part 1
(Elsevier, 1964)
When oxidized with lead tetraacetate 1-heptanol and 1-octanol undergo cyclization to give as major products the corresponding 2-alkyltetrahydrofurans, accompanied by a small amount of the isomeric tetrahydropyran derivatives. ...
Transformations of 2-alkylidene-4-oxothiazolidine vinyl bromides initiated by bromophilic attack of neutral and anionic nucleophiles
(Oxford : Pergamon-Elsevier Science Ltd, 2010)
Vinyl bromides derived from 2-alkylidene-4-oxothiazolidines represent a class of vinyl halides, which readily undergo a bromophilic attack by a range of nucleophiles. With Ph(3)P, AcS(-), CN(-), I(-), F(-), Ac(2)CH(-) and ...
Corrigendum to: Organocatalyzed Tsuji-Trost reaction: a new method for the closure of five- and six-membered rings (vol 65, pg 10485, 2009)
(Oxford : Pergamon-Elsevier Science Ltd, 2010)