Studies on synthesis of 10,11-dihydro-5H-dibenzo[a,d]cycloheptene derivatives. IV. Photoreactions of 5-substituted-5H-dibenzo[a,d]cycloheptenes with 1,2-substituted olefins and the stereostructures of the cycloaddition products.
The photoreactions of 5H-dibenzo[a, d]cyclohepten-5-one (la) and its 5-substituted derivatives (lz and ly) with olefins such as maleates, acrylates and crotonate gave the cycloaddition products (3a-e) in yields of 4-82%. Inversion reactions of the adducts (3b and 3c) with bases were carried out for the purpose of investigating the thermodynamic stability of the cycloadducts and the corresponding isomeric products (3b-t and 3c-f) were obtained. The stereostructures of the cycloaddition products and the isomeric products were determined by means of nuclear magnetic resonance (NMR) spectroscopy.
Photochemistry of supramolecular complex formed by trans-stilbene and the metal–organic coordination polymer
作者:Veronica V. Semionova、Evgeni M. Glebov、Valeri V. Korolev、Sergey A. Sapchenko、Denis G. Samsonenko、Vladimir P. Fedin
DOI:10.1016/j.ica.2013.09.048
日期:2014.1
Supramolecular adduct consisting from the metal-organic framework (MOF) [Zn-4(dmf)(ur)(2)(ndc)(4)] (ndc(2) is 2,6-naphtalenedicarboxylate, ur is urotropin, and dmf is N,N'-dimethylformamide) and trans-stilbene was synthesized and its photochemistry was studied. The quantum yield of trans-cis photoisomerization of stilbene in adduct (0.2) was found to be an order of magnitude higher than for crystalline trans-stilbene and comparable with that in organic solvents. The results demonstrate that the creation of MOFs adducts with organic photochroms is a prospective approach for the creation of new hybrid photochromic materials. (C) 2013 Elsevier B.V. All rights reserved.
TETRAPHENYLCYCLOBUTADIENE DERIVATIVES. I. TETRAPHENYLCYCLOBUTADIENE NICKEL BROMIDE COMPLEX