| 摘要 |
<p>1,201,090. 1,4 - Bis - [benzoxazolyl - (2<SP>1</SP>)]- naphthalenes. FARBWERKE HOECHST A.G. 27 July, 1967 [27 July, 1966; 6 July, 1967], No. 34605/67. Heading C2C. [Also in Divisions C3 and Dl] Novel compounds of the general formula wherein R is H, C 1-18 alkyl, cycloalkyl, hydroxyalkyl, alkoxyalkyl, aralkyl, N,N-dialkylaminoalkyl or a trialkylammonium group are prepared (a) by reacting 1 mole of 1,4-naphthalene dicarboxylic acid halide with at least 2 moles of an o-aminophenol of the general formula and the resulting bisamide is heated to above 200‹ C. in an inert atmosphere in a solvent having a boiling point above 200‹ C. to effect cyclization and, if desired, any carboxylic ester groups present are saponified, or (b) a 1,4-bis- [carbomethoxy - benzoxazolyl - (2<SP>1</SP>)] naphthalene compound of general formula is trans-esterified with an alcohol of boiling point at or above 78‹ C. in the presence of the corresponding alcoholate and, if desired, any dialkylamino group present is quaternized by means of an alkylating agent. In process (a) the dicarboxylic acid chloride is preferably used. The bisamide obtained may be heated in an inert atmosphere with a catalyst such as ZnCl 2 or p-toluene sulphonic acid in an isomeric mixture of trichlorobenzenes as solvent. The trans-esterification may be performed in the presence of a catalyst. In the Examples: (1) naphthalene dicarboxylic acid is converted to the acid chloride using SOCl 2 and then is reacted with 3-amino-4-hydroxybenzoic acid methyl ester to yield a diamide which is cyclised using ZnCl 2 as catalyst to give 1,4-bis-[5<SP>1</SP>-carbomethoxy - benzoxazolyl - (2<SP>1</SP>)] - naphthalene. The latter compound is converted (Example 2). by trans-esterification with n-octanol to 1,4-bis [5<SP>1</SP>-carbo-octoxybenzoxazolyl-(2<SP>1</SP>)]-naphthalene.</p> |
