78531-60-9Relevant articles and documents
Norrish II reactions of liquid-crystalline ketones. Comparison between smectic B and solid phase order and control of photoproduct distributions
Furman, Inna,Butcher, Raymond J.,Catching, Robert M.,Weiss, Richard G.
, p. 6023 - 6030 (2007/10/02)
The Norrish II photoreactions of trans-1-(4-heptanoylphenyl)-4-heptylcyclohexane (2a) and trans-1 heptyl-4-(4-nonanoylphenyl)cyclohexane (2b) have been examined in their isotropic, smectic B, and solid phases. The smectic phases have been characterized by optical microscopy, differential scanning calorimetry, and X-ray diffraction. Solid and smectic phase order, probed by deuterium NMR spectroscopy of 2 deuteriated at the methylene α to the carbonyl group, is correlated with the photochemical results. The apparent absence of a directing influence of the smectic B phases on the course of the Norrish II reactions of 2 is attributed to the local fluidity afforded the methylene groups of the alkyl chains. The solid phase influence on the distribution of Norrish II photoproducts is significant and indicates that a small amount of motional freedom persists in the alkyl chains even after bulk crystallization.
Synthesis and Liquid Crystalline Phases of Pyridazine Derivatives I
Liang, Jason C.,Cross, Julie O.
, p. 123 - 130 (2007/10/02)
Seven pyridazine compounds were synthesized.The compounds have a general structure R-X-Y-PZ-R', where PZ is 3,6 disubstituted pyridazine ring, X and Y are either trans cyclohexyl or phenyl rings, R and R' are n-alkyl groups.The structure assignments were confirmed by carbon 13 nmr.Their liqiuid crystalline properties were evaluated.All of them have mesophases with a broad temperature range.
KETONES-NEMATOGENS WITH MODERATE NEGATIVE DIELECTRIC ANISOTROPY AND HIGH CLEARING POINTS.
Osman,Huynh-Ba
, p. 141 - 152 (2007/10/02)
Anisotropic ketones whose rigid cores contain phenyl and cyclohexyl units were synthesized. The carbonyl group was incorporated either in the terminal substituents or in the link between the core units. The mesomorphic behavior of these ketones is described and correlated with their chemical structure. The 1-(4-alkanoylphenyl)-4-trans-alkylcyclohexanes as well as the 1-(4-alkanoylphenyl)-4-trans-alkanoylcyclohexanes show nematic phases. In contrast to laterally substituted compounds, these ketones have clearing points which are higher than those of the corresponding hydrocarbons. Another advantage of these nematogens is the ease of synthesis.
SYNTHESIS OF TRANS-4-ALKYL-1-PHENYLCYCLOHEXANES AND THEIR DERIVATIVES
Bezborodov, V. S.,Bubel', O. N.,Konovalov, V. A.,Ptashnikov, Yu. L.
, p. 1479 - 1483 (2007/10/02)
The alkylation of benzene by 1-alkanoyl-2-chlorocyclohexanes and 1-alkanoyl-1-cyclohexenes leads to the formation of cis- and trans-4-alkanoyl-1-phenylcyclohexanes, the yields of which increase with increase in the reaction temperature. trans-4-Alkyl-1-phenylcyclohexanes were obtained from 4-alkanoyl-1-phenylcyclohexanes and also from the products from the reaction of 4-alkylcyclohexanones with phenylmagnesium bromide.Some mesomorphous derivatives of these hydrocarbons were synthesized.
CONVENIENT SYNTHESIS OF 4-(TRANS-4 prime -N-ALKYLCYCLOHEXYL) BENZOIC ACIDS.
Szczucinski,Dabrowski
, p. 55 - 64 (2007/10/02)
A convenient method of obtaining 4-(trans-4 prime -n-alkylcyclohexyl) benzoic acids from alkanoyl chlorides, cyclohexane and benzene is described. Homologous series of above mentioned acids and their nitriles with alkyl tail 2 to 10 carbon atoms were prepared and temperatures of their phase transitions were determined.
