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The synthesis of new phenyl substituted derivatives ( 2) of α -hydrazino-alkylphosphonic acids by Lewis acid–mediated addition of dialkylphosphite to hydrazones, derived from benzoylhydrazines and benzaldehydes, is described. Reactions were successfully promoted by boron trifluoride etherate under mild conditions in methylene chloride at room temperature.

The structures of methyl 5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoate, C15H9ClF3N3O5, (I), methyl 2-chloro-5-[3-methyl-2,6-dioxo-4-(trifluoromethyl)-1,2,3,6-tetrahydropyrimidin-1-yl]benzoate, C14H10ClF3N2O4, (II), and 2-[4-chloro-2-fluoro-5-(prop-2-ynyloxy)phenyl]-4-(trifluoromethyl)piperidine-2,6-dione, C15H10ClF4NO3, (III), are similar in their dihedral angles and in the distances between the farthest two atoms. There are two independent molecules in the structure of (I). The dihedral angles between the two aromatic rings in each molecule in (I), between the benzene and tetrahydropyrimidine rings in (II), and between the benzene ring and the five-atom planar portion of the piperidine-2,6-dione ring in (III) are 80.78 (11)/89.75 (11), 89.13 (9) and 87.52 (13) degrees , respectively. The distances between the farthest two atoms, viz. O...F in the two molecules of (I), and Cl...F in (II) and (III), are 11.763 (7)/11.953 (6), 10.734 (10) and 10.889 (9) A, respectively. In all three crystal structures, the molecules are linked to generate sheets of molecules via C-H...O interactions.

Reaction of camphor-derived exo-formyl [2.2.1]bicyclic carbinol with various alkyl primary amines gave regio- and stereo-specific [3.2.1]bicyclic α-amino ketones. A detailed mechanism of the reaction was discussed. This reaction was further applied to the preparation of some camphor-derived oxazaborolidines, one of which proved to be an efficient chiral catalyst for the asymmetric borane reduction of prochiral aryl ketones at room temperature.