A novel phosphorus–carbon bond formation by ring opening with diethyl phosphite of oxazolines derived from serine

Crystal structure of diethyl [(4-chloroanilino)(4-hydroxyphenyl)methyl]phosphonateN,N-dimethylformamide monosolvate

In the title compound, C17H21ClNO4P·C3H7NO, the dihedral angle formed by the aromatic rings is 83.98 (7)°. In the crystal, O—H...O, N—H...O and C—H...O hydrogen bonds link the molecules into double layers parallel to (011).

Synthesis of New Racemic α,α-Diaminocarboxylic Ester Derivatives

New racemic methyl or ethyl α-aminoglycinate derivatives were synthesized by N-alkylation of amines (aniline, 4-methylaniline, 2-methylaniline, 2,4-dimethoxyaniline, 2-nitroaniline, 4-chloro-2-fluoroaniline, 2-naphthylamine, benzylamine, N,N-dibenzylamine, and cyclohexylamine) with methyl or ethyl α-azidoglycinate.

Ethyl [(2-hydroxy-phen-yl)(pyridinium-2-ylamino)meth-yl]phospho-nate methanol solvate

In the title compound, C(14)H(17)N(2)O(4)P·CH(3)OH, the planes of the pyridinium-2-ylamino and 2-hydroxy-phenyl groups form a dihedral angle of 75.6 (1)°, with the pyridinium NH group and the 2-hydroxy-phenyl OH group pointing in opposite directions. Three intra-molecular hydrogen bonds are observed. Two phospho-nate and two methanol mol-ecules are connected by O-H⋯O hydrogen bonds as a centrosymmetric dimeric cluster, and inter-act further with other dimeric clusters via N-H⋯O, O-H⋯O and C-H⋯O hydrogen bonds and C-H⋯π inter-actions, resulting in a sheet structure.

Catalytic asymmetric addition of β-keto phosphonates to an activated imine—formation of optically active functionalized phosphonate α-amino acid derivatives

The direct stereoselective addition of an activated imine to beta-keto phosphonates in the presence of chiral Lewis acid complexes is developed. The evaluation of different activated imines shows that an N-tosyl-alpha-imino ester adds in a diastereo- and enantioselective fashion to beta-keto phosphonates activated by especially chiral copper(II)-bisoxazoline complexes. An evaluation of Lewis acids, chiral ligands and reaction conditions, such as solvent, bases and other additives, shows that high yields, moderate diastereoselectivity and good enantioselectivity are obtained. The scope of the reaction is demonstrated for the reaction of beta-keto phosphonates and finally, the mechanism for the catalytic stereoselective step is presented.