Ru and Sm catalyzed polyaddition of dialdehydes to give polyesters. Application of Tishchenko type reactions to polymer synthesis

摘要

RuH2(PPh3)(4) catalyzed Tishchenko type polyaddition of terephthalaldehyde gives aromatic polyester (1), which contains three structural units, [OCH2-C6H4-CH2O] (1a), [OCH2-C6H4-CO] (1b), and [CO-C6H4-CO] (1c). H-1-NMR spectrum shows the presence of the three units in a 1 : 2 : 1 ratio. Isophthalaldehyde also undergoes similar polyaddition to give another aromatic polyester (2), while 1,12-dodecanedial gives an aliphatic polyester (3) containing the following structural units: [OCH2-(CH2)(10)-CH2O] (3a), [OCH2-(CH2)(10)-CO] (3b), and [CO-(CH2)(10)-CO] (3c). The above polymers have M-n of 2.7 x 10(3)-5.4 x 10(3) and M-w of 4.3 x 10(3)-9.7 x 10(3), respectively. Mixtures of terephthalaldehyde and 1,12-dodecanedial produce copolymers, which contain the units 1a-1c and 3a-3c in a random sequence. In the copolymerization, terephthalaldehyde shows a strong tendency to give 1c units, whereas 1,12-dodecanedial predominantly affords 3a units. SmI2 also catalyzes polyaddition of terephthalaldehyde to give the corresponding polyester with M-n of 1.7 x 10(3) and M-w of 3.7 x 10(3), respectively. (C) 1997 John Wiley & Sons, Inc.