Salts of the scissor-shaped racemic host 1,1′-binaphthyl-2,2′-dicarboxylic acid with amines: structure and thermal stability

Ayesha Jacobs, Nikoletta B. Báthori, Rodriguez Y. Kabwit, Edwin Weber
2014 CrysteEngComm  
The salts formed between racemic 1,1′-binaphthyl-2,2′-dicarboxylic acid (BNDA) and the amines diethylamine (DEA), di-n-butylamine (DBA), cyclohexylamine (CHA) and dicyclohexylamine (DCHA) are reported. Structure 1, (BNDA 2− )(2DEA + ), and 2a, (BNDA 2− )(2DBA + ), resulted from slow evaporation of a solution of BNDA in the respective amine. A competition experiment whereby BNDA was dissolved in a mixture of 60% DEA and 40% DBA resulted in a polymorph of 2a, namely 2b. Slow evaporation of dilute
more » ... solutions of BNDA with CHA and DCHA resulted in a mixed salt solvate 3, (BNDA 2− )(3CHA + )(C 7 NO 2 H 11 − )·CHA·H 2 O, and a salt solvate, 4, (BNDA 2− )(2DCHA + )·CH 3 OH·H 2 O, respectively. For all the experiments methanol was used as a co-solvent due to BNDA insolubility with the amines. In structure 3 one of the CHA guests reacted with carbon dioxide in the atmosphere to form a carbamate anion, C 7 NO 2 H 11 − . The kinetics of desolvation for salts 1, 2a and 2b were also determined.
doi:10.1039/c3ce42215a fatcat:h7kmgrrtujenfd7ahp2i7hjlke