Evaluation of the Catalytic Capability of cis‐ and trans‐Diquinoxaline Spanned Cavitands

• Published in: European journal of organic chemistry 2019-09, Vol.2019 (36), p.6261-6268
• Main Authors: Inoue, Mami, Kamiguchi, Shinsuke, Ugawa, Katto, Hkiri, Shaima, Bouffard, Jules, Sémeril, David, Iwasawa, Tetsuo
• Format: Article
• Language: English
• Subjects: Alkynes; Catalysis; Catalytic activity; Cavitands; Comparative studies; Dimerization; Gold; Homogeneous catalysis; Introverted ligands; Organic chemistry; Rhodium; Selectivity; Structure‐activity relationships
• ISSN: 1434-193X; 1099-0690
• DOI: 10.1002/ejoc.201901058

Three new cis‐diquinoxaline spanned cavitands were successfully synthesized. These cis‐diphosphinated derivatives were applied in homogeneous gold‐catalyzed dimerization and hydration of alkynes as well as rhodium‐catalyzed styrene hydroformylation. The results were ranked with those obtained with their trans‐diphosphinated isomeric analogues. The structure‐activity relationship employing these two cavitands reveals that the cis‐ or trans‐positioning of the catalyst centers directly influences cooperation between the two metallic atoms to control catalytic activity, reaction profile, and product selectivity. This comparative study provides us an intellectual basis for future catalytic cavitand chemistry and homogeneous catalysis. Synthesis of new cis‐typed bis‐phosphorus cavitands is described, including a description of their catalytic capability in transition‐metal‐catalyzed reactions. The catalysis of cis‐versions were compared to the corresponding trans‐isomeric bis‐phosphorus cavitands, which revealed that different shape of compartments gave different profile of reactivity and product distribution.