171513-93-2Relevant academic research and scientific papers
1H and 13C NMR Study of Stereoisomers of 3-(Arylpropenylidene)isobenzofuran-1(3H)-ones
Sveshnikov, Nikolay N.,Nikulin, Victor I.
, p. 755 - 757 (1995)
A study of the 1H and 13C NMR spectra of a series of E,E- and Z,E-isomers of 3-(arylpropenylidene)isobenzofuran-1(3H)-ones was carried out.The E,E- and Z,E-isomers 1a-d and 2a-d were recognized by the local anisotropy effect of the double and triple bonds of the substituents experienced by H-4 in E,E-isomers; in Z,E-isomers, in contrast to their E,E-analogues, upfield shifts of C-4 and C-8 due to the H-H γ-cis effect were observed. - Keywords: NMR; 1H NMR; 13C NMR; 3-(arylpropenylidene)isobenzofuran-1(3H)-ones; stereoisomers
Regioselective synthesis of (E)-5-(tributylstannylmethylidene)-5H-furan-2- ones and (E)-3-(tributylstannylmethylidene)-3H-isobenzofuran-1-ones: Easy access to γ-alkylidenebutenolide and phthalide skeletons
Duchene, Alain,Thibonnet, Jerome,Parrain, Jean-Luc,Anselmi, Elsa,Abarbri, Mohamed
, p. 597 - 607 (2007/12/25)
Regio- and stereoselective synthesis of γ-alkylidene-butenolides and γ-alkylidenephthalides has been achieved through the palladium-catalysed tandem cross-coupling/cyclisation reactions of tributylstannyl-3-iodopropenoate or the 2-iodo benzoate derivatives with tributyltinacetylene. Iododestannylation occurred with inversion of the configuration of the exocyclic double bond in the case of butenolides, but with retention of configuration for the phthalide. The selectivity observed in the Stille reaction was found to be dependent on the nature of the vinyl or the aryl halide. Georg Thieme Verlag Stuttgart.
