ALTERNATING COPOLYMERS OF FUNCTIONAL ALKENES WITH CARBON-MONOXIDE

The alternating copolymerization of functional alkenes, CH2 = CH(CH2)( x)OH (x = 2, 3, 4, 9), CH2 = CH(CH2)(x)COOH (x = 1, 2, 4, 8), and 4-al lylanisole, with carbon monoxide was achieved by using [Pd(Me-DUPHOS)( MeCN)(2)](BF4)(2) [Me-DUPHOS = 1,2-bis(2,5-dimethylphospholano)benzene ] as the catalyst. The resultant polymers were optically active with i sotactic sequences in the backbone. With most alkenes, the polymers ha d poly(1,4-ketone) and/or ''regular'' poly(spiroketal) (i.e., 1,6-diox aspiro[4.4]nonane) enchainments. However, with 4-penten-1-ol and 3-but en-1-ol, the participation of the pendant hydroxyl group in intrachain reactions led to the formation of unusual polycyclic repeating units in the backbone. A comparison of [Pd(Me-DUPHOS)(MeCN)2](BF4)(2) with [ Pd(DPPP)(MeCN)(2)](BF4)(2) [DPPP = 1,3-bis(diphenylphosphino)propane] indicated that the former was a significantly better catalyst for the alternating copolymerization of alkenols and alkenoic acids with carbo n monoxide.