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Abstract: An organometallic transition state analogue for the asymmetric reduction of acetophenone with a Cp* Rh complex has been synthesised and structurally characterised (3). This complex has a chiral N,N'-chelate Ligand with a styrene side chain to allow its incorporation into organic polymers. The remaining coordination site is occupied by a methyl-phenylphosphinato ligand. This ligand acts asa pseudosubstrate which mimics acetophenone. The conformation and configuration of 3 in the crystal are in excellent agreement with the postulated transition structure. Following the protocol of molecular imprinting, complex 3 was co-polymerised with ethylene glycol dimethacrylate in the presence of a porogen. The resulting polymer P3 was ground and sieved and the phosphinato ligand was substituted with a chloro ligand to generate a shape-selective cavity in proximity to the catalytically active metal centre. When tested for its ability to catalyse the reduction of acetophenone and related substrates the imprinted polymer P3 showed a significantly higher activity than a control polymer P2 without a cavity. Excellent enantioselectivities (up to 95% ee) were obtained, with the catalyst P3 being more selective than the respective control catalyst P2 (Delta ee = 2-9%). Competition experiments with acetophenone and a second co- substrate have revealed that the cavity generated with the phosphinato ligand is specific for acetophenone