Aydee Fuentes

Oligomerization of benzylic alcohols and its mechanism

A number of cyclic (5a-b) and linear (3a-c; 4b-c) oligomers arose from benzylic alcohols have been synthesized by treatment of 1a-c with a bentonitic earth. A mechanism for the formation of both cyclic and linear oligomers is proposed based on the isolation of the key intermediate; the ethers 2a-c.

Synthesis of (Tetrahydrofuranyl)methyl-1,2,3-triazoles Through Alkyne–Azide Cycloaddition Catalyzed by a Dithioic Acid Copper(I) Complex

Abstract (Tetrahydrofuranyl)methyl-1,2,3-triazoles were synthesized from tetrahydrofurfuryl tosylate and several alkynes in the presence of catalytic amounts of a 3-hydroxy-3-phenyl-2-propenendithioate-bis(triphenylphosphine) copper(I) complex. The reaction process is carried in out under mild conditions, and bases or reducing agents were not used. The reaction afforded the 1,4-regioisomers in excellent yields.

2D 1H and 13C NMR evidences of the [2+2] autodimerization of 2-benzyl-5-benzylidene cyclopentanone yielding two different diphenyl, dispiro cyclobutane derivatives

The ene-ene [2 + 2] cycloaddition of 2-benzyl-5-benzylidenecyclopentanone proceeds smoothly and spontaneously in benzene-d6 or deuteriochloroform solution to give two different diphenyl dispiro [4.1.4.1] dodecan-4,11-diones. Detailed 1H and 13C 2DNMR spectroscopy (COSY, HMQC, HMBC) were performed in order to prove the existence in solution of two cyclobutane derivatives, one a previously described photodimer obtained by the UV irradiation of crystals of 2-benzyl-5-benzylidenecyclopentanone.

1H, 13C 2D NMR and X-ray studies of the products of the reaction between dibenzylidencyclohexanone and 6-amino-1,3-dimethyl uracil

The reaction of the 6-amino-1,3-dimethyl uracil with the dibenzylidencyclohexanone (1), provided three adducts whose structures result from nucleophilic attack yielding the monoadduct 3 and two isomeric bisadducts (4 and 5) in moderate yields (50-60%). The structures obtained in this study were elucidated with 2D high resolution NMR experiments, variable temperature NMR and X-ray crystallographic studies. In compound 3, the tricyclic skeleton is essentially planar and the cyclohexane ring addopts an envelope conformation. The structures 4 and 5 correspond to two isomeric spiro compounds.

A New Synthesis of Desmethoxyencecalin

Abstract A new synthesis of the title compound using aryllithium salts as key intermediates is described. The synthetic approach is mainly based on a cyclization reaction that mimics the process by which is believed benzopyran rings are formed in nature.