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Abstract-Several cinchona based squaramide catalysts were applied in asymmetric Michael addition of α-nitroethylphosphonates to acrylic acid aryl esters, resulting in high yield and enantioselectivity. The absolute configuration of one of the quaternary α-nitrophosphonate adducts was deduced from its experimental and calculated CD spectra. The adducts were reduced to their cyclic aminophosphonates by catalytic hydrogenation.

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