Hydroformylation process using novel phosphine-rhodium catalyst system

Abstract From the Canadian patent

Disclosed are bis-phosphine compounds having the general formula, (see fig. I), wherein: each of A1, A2, A3 and A4 is an arylene radical wherein (i) each phosphorus atom P is bonded to a ring carbon atom of A1 and A2 and to a ring carbon atom of A3 and A4, (ii) A1 and A2, and A3 and A4 are bonded to each other by ring carbon atoms and (iii) each of the residues, (see fig. II) and (see fig. III) constitutes a 5-membered ring;, each of A5 and A6 is an arylene radical wherein A5 and A6 are bonded to each other and to residues R1-C-R2 and R3-C-R4 by ring carbon atoms and R1-C-R2 and R3-C-R4 are connected to each other through a chain of 4 carbon atoms; and, R1, R2, R3 and R4 each represents …