Tetrahydrophthalic Anhydride Formation

Endomethylene tetrahydrophthalic anhydride and the methyl derivate are also claimed for imide formation with aminoethanol [209]. The reaction of the endomethylene tetrahydrophthalic anhydride with hexahydro-p-aminobenzoic acid followed by a esterification with ethylene glycol and terephthalic acid yields an unsaturated imidoester curable by Michael addition with polyamines [210]. 

Reaction of 4,5-dimethyl-tetrahydrophthalic anhydride with methyl dithiocarbazate results in formation of hydrazide (110), which is cyclized in hot sulfuric acid to the 5,2,3-benzothiadiazocin-1,6-dione (111), as shown in Scheme 18 <88MI 925-0i>. Similar cyclizations are reported to occur using 3-nitrophthalic <87MI 925-01 > and quinolinic anhydrides <87MI 925-02>. 

Tetrahydrophthalic anhydride (7.775) was converted directly to c -5-amino-3-cyclohexene carboxylic acid, 7.77 by reaction with ammonia and then NaOCl. 107.14 If 7.775 is first opened, isomerized, and converted to the trans-diester (7,775), formation of the trans-anhydride is possible (7.179). This anhydride was then converted to trons-5-amino-3-cyclohexene carboxylic acid, 7.180. A related route converted 7.175 to racemic cis-methyl 2-carboxylcyclohex-4-enoate, which was resolved with cinchonidine.lO The resolved (+) or (-)-half-esters were then converted to (-)-7.77 or (+)-7.77. 

For the determination of butadiene in gaseous mixtures< > a known volume of gas is placed in contact with a known amount of maleic anhydride. Butadiene reacts with maleic anhydride with the formation of tetrahydrophthalic anhydride. After dissolution, the amount of unreacted maleic anhydride can be determined polarographically. 

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