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An efficient high yielding chemoselective synthesis of eleven novel 1-chloro-2-arylcyclohexenes employing the Suzuki cross coupling of 1-bromo-2-chlorocyclohexene with eleven different aryl boronic acids and Pd(dppf)Cl2·CH2Cl2 catalyst is reported.

A one-pot synthesis of some novel anionic scaffolds: the substituted-4-((4-trimethylsilyl-1H-1,2,3-triazol-1-yl)methyl)-2H-chromen-2-one is reported. Reaction of 10 different substituted bromomethylcoumarins with trimethylsilylacetylene and sodium azide in the presence of copper(I) iodide catalyst gave the corresponding heteroaryl conjugates: the substituted-4-((4-trimethylsilyl-1H-1,2,3-triazol-1-yl)methyl)-2H-chromen-2-one in 70-92% yields. The structures of the synthesized compounds have been completely characterized by spectral and elemental analyses. For the first time, the representative single-crystal X-ray structure analysis of 6-methoxy-4-((4-trimethylsilyl-1H-1,2, 3-triazol-1-yl)methyl)-2H-chromen-2-one is reported which confirms the formation of anionic synthon which bears the trimethylsilyl-group.

Five-and six-membered α-trimethylsilyl-α,β-unsaturated cycloalkenones were prepared by the Wurtz-Fittig coupling reaction of the corresponding 6-bromo-1,4-dioxaspiro[4,n]cycloalk-6-enes with sodium and chlorotrimethylsilane. Upon treatment with anhydrous AlCl 3 , the compounds underwent carbon-silicon bond scission to yield a novel class of compounds: the 2-(hydroxydimethylsilyl)cycloalk-2-enones.

New substituted derivatives of 5-vinyl-1,3-dimethylbarbituric acid were synthesised and evaluated for liquid crystal properties. Two sets of molecules were prepared. One end of all the molecules possesses the 1,3-dimethylbarbituric core. The first set comprises biphenyl ethers, 4a-n and the second set biphenyl esters, 5a-g. Liquid crystalline properties were investigated by POM and DSC techniques. All the compounds exhibited enantiotropic smectic A and nematic mesophases. The LC properties were found to depend on the spacer and terminal alkoxy-chain and alkoxy-ester moiety of the molecules. Smaller alkyl chain members showed a smectic phase, while higher alkyl chain members showed a nematic phase. ARTICLE HISTORY