Thiophene-5,5-dioxides molecular structure

Dipolar cycloaddition of 2,4-(trimethylsilyl)- and 2,4-(trimethylgermyl)-substituted thiophene-1,1-dioxides as well as silylated 2,2 -bithiophene-1,1-dioxides was investigated. It was shown that only the C(4)=C(5) double bond of 2,4-disubstituted thiophene-1,1-dioxides interacts with acetonitrile oxide to give thienoisoxazoline dioxides. Bithiophene derivatives were inactive or their reaction with nitrile oxide was accompanied by desilylation. Cycloaddition of benzonitrile oxide with all mentioned sulfones did not occur. The molecular structure of 3a-methyl-5.6a-bis(trimethylgermyl)-3a,6a-dihydrothieno 2.3-c/ isoxazole 4,4-dioxide was established by X-ray diffraction (263). ... 

The observed spectra of some duroquinone-nickel complexes with olefins have been correlated by means of semiquantitative molecular-orbital theory by Schrauzer and Thy ret (48). In the case of n complexes of polynuclear hydrocarbons, such as naphthalene and anthracene, although their spectra are recorded, no conclusions have been drawn with regard to structure nor has any theoretical work been reported. Similar remarks apply to complexes of nonalternant hydrocarbons such as azulene. Although innumerable complexes of olefins with various transition metals are known and admirably reviewed (84), no theoretical discussion of even a qualitative nature has been provided of their electronic spectra. A recent qualitative account of the electronic spectra of a series of cyclopentadienone, quinone, and thiophene dioxide complexes has been given by Schrauzer and Kratel (85). 

Molecular structure of thiophene-1,1-dioxides, thiophcnc-.S -oxidcs and their derivatives 02KGS725. 

E. Lukevics, P. Arsenyan, S. Belyakov and O. Pudova, Molecular structure of thiophene-1,1-dioxides, thiophene-5-oxides and their derivatives, Chem. Heterocycl. Compd., 38, 632-645 (2002). 

S. Destri, M. Pasini, W. Porzio, A. Gavezzotti and G. Filippini, X-ray diffraction studies and computer simulations of the crystal and molecular structure of 2,5-di-(9,9-dimethylfluoren-2-yl)-3,4-dihexyl-thiophene-l,1-dioxide, a photoluminescent material, Cryst. Growth Des., 3, 257 - 262 (2003). 

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