Potential side-chain liq. crystal acrylate monomers prepn. - by reaction of 4-hydroxybenzoic acid with 4-alkoxyphenol or bisphenol then with di:bromo:alkane and then with alkali (meth)acrylate

摘要

The prodn. of potential side chain liq. crystalline acryalte monomers of formula CH2=CR''-COO-R'-Phe-COO-Phe-OR (I) comprises (a) esterification of p-hydroxybenzoic acid with p-alkoxyphenols or bis-phenols of formula HO-Phe-R in the presence of H2SO4 and H3BO3 to give an ester of formula Br-R'-Br at boiling temp. in the presence of alkali carbonate and KI to give the corresp. bromoalkoxy ester and (c) reaction with K (meth)acrylate at 60 deg.C in a solvent such as acetone, MEK, HMPT or DMF. In (I) Phe = 1,4-phenylene; R = -OH, -OCmH2m+1 (with m = 1-8) or -Phe-Ph; R' = -(CH2)n- (with n = 1-12); R'' = H or Me. USE/ADVANTAGE - (I) are useful for the prodn. of highly uniform highly ordered side chain liq. crystal polymers (SCLCP). W.r.t. prior-art syntheses, the process is less expensive and gives (I) in higher overall yield (x 5), due to the modified reaction sequence which eliminates competition between functional gps. and thus eliminates the need to purify intermediate stages. In the above process, the central structural unit is combined with the ''wing gps.'' in the first stage rather than the la