Phosphorus-nitrogen compounds: Part 45. Vanillinato-substituted cis-and trans-bisferrocenyldispirocyclotriphosphazenes: Syntheses, spectroscopic and crystallographic characterizations

The nucleophilic replacement reactions of one equimolar amount of the cis- and trans-bisferrocenyldispirocyclotriphosphazenes (1 and 2) with the one equimolar amount of the potassium salt of 4-hydroxy-3-methoxybenzaldehyde (potassium vanillinate) produce mono-vanillinato phosphazenes (3 and 4). When these reactions were carried out with the one equimolar amount of 1 and 2, and two equimolar amounts of potassium vanillinate gave bis-vanillinato ferrocenylphosphazenes (5 and 6). The structures of the new phosphazenes were characterized by FTIR, MS, H-1, C-13 and P-31 NMR spectral data. The solid-state structures of 3, 4, 5 and 6 were clarified by single crystal X-ray diffraction techniques. All the phosphazenes have stereogenic phosphorus atoms. Compound 3 has a pseudo asymmetric center. The absolute configurations of all the compounds were examined using X-ray crystallography. The chiral properties of 3 and 4 were also investigated by P-31 NMR spectroscopy upon the addition of the chiral solvating agent (S)-(+)-2,2,2-trifluoro-1-(9'-anthryl)ethanol, CSA. (C) 2018 Elsevier B.V. All rights reserved.