Phthalocyanine compounds substituted with steric hindrance groups have been synthesized: octakis(2-ethyl-hexy1)phthalocyanine (1 b) and bis[octakis(4-octadecyloxyphenyl)phthalocyaninato]lutetium(111) complex (2d). These compounds exhibit a wide temperature range of discotic liquid-crystalline properties. Each of these compounds shows a discotic tetragonal disordered columnar mesophase (Dtet.d) or a discotic plain rectangular disordered columnar mesophase [Drd(P2rn)] with a lattice very close to tetragonal. This Drd(P2rn) phase is a novel discotic mesophase that has not been reported to date. It was found that the introduction of the steric hindrance groups, 2-ethylhexyl (b) and 4-octadecyloxyphenyl (d), tend to induce the appearance of the Dtet.d phase.

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Novel bis(phthalocyaninato)lutetium(iii) complexes substituted with long n-alkyl chains have been synthesized. These complexes, la-c, show three kinds of discotic mesophase (D,,, Doh.,, and DJ. Also la-c display the three primary colours (red, green, blue) of electrochromism in their solutions. The solutions of oxidized species of la-c are nearly red, although those of conventional bis( phthalocyaninato)lutetium(iii) complexes are orange.~ Hexadeca-n-alkyl-substituted complexes of bis( phthalocyaninato)lutetium(rrr) (la-c) have been synthesized. These com-Paper 3,422306;

The condensation reaction of lignin is believed to interfere with delignification in alkaline pulping processes, without any clear evidence, which has motivated us to quantitatively revisit it. This paper is the first of a series, and hence we employed the simplest model system using 4-hydroxymethyl-2-methoxyphenol (vanillyl alcohol, Va) and 2-methoxy-4-methylphenol (creosol, Cr) under soda cooking conditions. The α-5-type condensation product between these compounds [VaCr, 2-(4-hydroxy-3-methoxybenzyl)-6-methoxy-4-methylphenol] was identified and quantified as exclusive. VaCr was yielded with a mole amount of 24%, 46%, 62%, or 72% based on that of disappearing Va at a reaction time of 120 min when the ratio of the initial concentration of Cr to that of Va was 1.0, 2.5, 5.0, or 7.5, respectively. These yields and an HPLC analysis of the reaction solution obtained by a treatment of Va as the sole compound under the same soda cooking conditions suggested the formation of self-condensation products of Va even in the treatments containing Cr. The obtained results comprehensively suggested that the self-condensation of Va progresses more readily than the condensation between Va and Cr. The factors behind this will be the topic of our next paper.

The viscosities of poly(acrylic acid) (PAA) and poly(methacrylic acid) (PMA) have been measured in aqueous 0.25 M NaCl solutions at 5, \5, 25, 35, and 45oC as a function of various degrees of neutralization. The potentiometric titration data for these polycarboxylic acids in water at 5, 25, and 45°C are also reported. Both results indicate that the compact conformation of PMA at low degree of dissociation is more stabilized at lower temperatures. The origin of the hydrophobic interaction has been discussed and it has been suggested that any change of water structure around hydrophobic groups is not required to account for the pH-induced conformational transition of PMA.