Bimetallic alkoxides of praseodymium and neodymium with aluminum, viz., M[Al(-OC3H7i)(4)](3), where M = Pr(III)/Nd(III), have been used as catalysts in Meerwein-Ponndorf-Verley (MPV) reduction of 2-octanone and benzophenone in isopropanol to give their corresponding secondary alcohols. The reduction of ketones is investigated by following the absorption spectra involving 4f-4f transitions. During the MPV reduction the oscillator strengths (P) and the Judd-Ofelt intensity (T., X = 21 47 6) parameters corresponding to each 4f -4f band (H-3(4) --> D-1(2), H-3(4) --> P-3(0), H-3(4) --> P-3(1), and H-3(4) --> P-3(2) in praseodymium, and I-4(9/2) --> F-4(3/2) I-4(9/2) --> F-4(5/2), I-4(9/2) --> F-4(7/2), I-4(9/2) --> (4)G(5/2), and I-4(9/2) --> (4)G(7/2) in neodymium alkoxides) at different time intervals have also been calculated and used in the determination of rates. Rates were calculated in terms of complexation of ketone and isopropanol with M[Al(-OC3H7i)(4)](3) during the MPV reaction, from the changes in both absorbance and oscillator strength with time, and were found to be comparable, verifying the Judd-Ofelt theory. The stronger oxyphilicity of Pr(III) and Nd(III) in M[Al(-OC3H7i)(4)](3) than of their analogue Al(III) in Al(-OC3H7i)(3) made the bimetallic alkoxides better catalyst in MPV reduction of ketones. (C) 2004 Elsevier Inc. All rights reserved.