Linear‐selective hydroformylation of vinyl ether using Rh (acac)(2,2′‐bis{(di[1H‐indol‐1‐yl]phosphanyl)oxy}‐1,1′‐binaphthalene) – Possible way to synthesize 1,3‐propanediol.

Three bidentate phosphoramidite ligands were synthesized, characterized, and employed in Rh‐catalyzed hydroformylation of vinyl ethers. The complex Rh(acac)(2,2′‐bis{(di[1H‐indol‐1‐yl]phosphanyl)oxy}‐1,1′‐binaphthalene} (acac = acetylacetone) (Rh‐L4) was also synthesized and characterized. Rh‐L4 showed good regioselectivity for the hydroformylation of vinyl ethers under mild reaction conditions: 2 MPa of syngas, 1:1 (H2/CO) substrate/catalyst molar ratio 1000:1, and 60 °C. The linear selectivity was up to 98%, and in most cases was about 80%, with no hydrogenation product formation observed, which could be a potential way to synthesize 1,3‐propanediol. A mechanism study including density functional theory computational analysis showed that both Rh–H and CO insertion steps in the hydroformylation of vinyl ether were linear‐preferred in our catalyst system. [ABSTRACT FROM AUTHOR]