Poly(β-trimethylsilyloxy ester): A Degradable Polymer Based on Retro Mukaiyama Aldol Reaction

Herein, a new type of degradable poly(β-trimethylsilyloxy ester) prepared by the organocatalyzed Mukaiyama aldol polyaddition between bis(silyl ketene acetal)s and dialdehydes is reported. Specifically, the t-Bu-P₄ -catalyzed polyaddition between 1,2-bis[2-methyl-1-(trimethylsiloxy)prop-1-enyloxy]ethane (MTS₂ ) and 4,4'-biphenyldicarboxaldehyde (BPDA) or butane-1,4-diyl bis(4-formylbenzoate) (BDA) can produce poly(β-trimethylsilyloxy ester)s with number-average molar mass greater than 10 kg mol^-1 . For the first time, it is found that these poly(β-trimethylsilyloxy ester)s are degradable in solution in the presence of nucleophiles such as fluoride and cyanide anions. It is also found that the degradation behavior of poly(β-trimethylsilyloxy ester)s is highly dependent on the nature of the used catalyst and the bond scission in polymer is fundamentally rooted in the retro Mukaiyama aldol reaction mechanism.