Chiral periodic mesoporous copper(II) bis(oxazoline) phenylene–silica: A highly efficient and reusable asymmetric heterogeneous catalyst

• Novel chiral periodic mesoporous phenylene–silica is synthesized.
• High density of bis(oxazoline) moieties and surface area.
• Co-condensation with 1,4-bis(triethoxysilyl)benzene leads to porous material.
• Effective heterogeneous asymmetric catalyst in the benzoylation of 1,2-diol.
• Reusable for five cycles without loss of catalytic activity or enantioselectivity.

We describe the preparation of an effective and reusable heterogeneous asymmetric catalyst. A novel chiral periodic mesoporous phenylene–silica containing high density of bis(oxazoline) moieties is prepared by co-condensation method with 1,4-bis(triethoxysilyl)benzene. After copper(II) coordination, the material is extremely efficient on the kinetic resolution of the 1,2-diphenylethane-1,2-diol with persistent high enantioselectivities (91 - > 99%) and yields (46–43% in maximum 50% resolution) at least for five consecutive cycles. Characterization of the material after the catalytic experiments showed that the heterogeneous catalyst was very robust keeping the integrity of the structure.

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