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A library of easy‐to‐prepare and modular chiral P,N‐phosphoramidites based on [1,1′‐biaryl]‐2,2′‐diols and C1‐symmetric 1,2‐diamines has been designed and developed. The structures of the novel ligands have been elucidated by means of 2D‐NMR and confirmed in the solid state by X‐ray diffraction analysis. Stereoselectors of this type exhibited high enantioselectivities in Pd‐catalyzed allylic substitution reactions of (E)‐1,3‐diphenylallyl acetate with NaSO2pTol (up to 91 % ee), CH2(CO2Me)2 (up to 89 % ee), (C3H7)2NH (up to 94 % ee) and (EtO)2P(O)CH2NH2 as a novel nucleophile (up to 98 % ee). Ee values of up to 88 % and 72 % have been obtained in the Pd‐catalyzed desymmetrization of N,N′‐ditosyl‐meso‐cyclopent‐4‐ene‐1,3‐diol biscarbamate and in the Cu‐catalyzed 1,4‐conjugate addition of diethylzinc to chalcone, respectively. The reactions of P,N‐bidentate ligands with [Pd(Cod)Cl2] at molar ratios of L/M=1 and 2 have been studied using 1H, 13C, 13C‐1H HSQC, 13C‐1H HMBC, 1H‐1H COSY, 1H‐1H ROESY, DOSY and 31P NMR spectroscopy as well as HR ESI mass spectrometry.

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A straightforward synthesis of P-chiral polycyclic phosphines by an asymmetric Diels–Alder reaction of 1-alkyl-1,2-diphospholes and (5R)-(l-menthyloxy)-2(5H)-furanone (MOxF) is presented.