New reusable heterogeneous catalyst in the MPV reduction in cyclohexenones: moderate one-pot synthesis of cyclohexenols (effect of methyl substituents)

Abstract

Inorganic compounds grafted MCM-41 catalysts and the Meerwein-Ponndorf-Verley reduction (MPV) on these heterogeneous catalysts are very attractive subject areas in chemistry. New mesoporous In((OPr)-Pr-i)(3)-MCM-41 was tested for MPV reaction of cyclohexenones. Effect of methyl substituents on cyclohexenol yield was investigated. Also, reusability of catalyst was studied. Mesoporous In((OPr)-Pr-i)(3)-MCM-41 catalyzed MPV reduction in cyclohexenones to corresponding cyclohexenols in pretty good yields. Higher reaction times and lower alcohol yields for the methyl substitute cyclohexenones were obtained with In((OPr)-Pr-i)(3)-MCM-41 compared with the non-substitute cyclohexenone. Methyl substitute cyclohexenones as compared with non-substitute cyclohexenone compounds have lower activities that probably resulted from steric hindrance of alkyl group. Methyl group can create steric effect for cite accessibility of the catalyst. Moreover, In((OPr)-Pr-i)(3)-MCM-41 catalyst exhibited excellent recyclability for six MPV reduction round without significant loss of the reactivity. Also, the In((OPr)-Pr-i)(3) does not leach during the reduction reaction. Heterogeneous In((OPr)-Pr-i)(3)-MCM-41 was found as very influential catalyst for the preparation of cyclohexenol derivatives.