Synthesis and structures of new symmetrically and unsymmetrically substituted cyclodiphosphazanes

The reaction of lambda(3)-diazadiphosphetidine [ClPNt-Bu](2) (1a) with phen ols in the presence of triethylamine or as their sodium salts affords only cis-[(ArO)PNt-Bu](2) as isolable products; thus, several compounds where Ar O=2,6-dimethylphenoxy (2), 2-naphthoxy, 4-methoxy (3), 4-methoxyphenoxy (4) , 4-methylphenoxy (5), 4-t-butylphenoxy (6) and 1-anthryloxy (8) were synth esized. The reaction of 1a with 1 mor equivalent of 2,6-dimethyl phenol or 2-naphthol afforded the unsymmetrical derivatives [ClP(N-t-Bu)(2)P(OAr)], w here ArO=2,6-dimethyl phenoxy (9) or 2-naphthoxy (10), which could be chara cterized by P-31 NMR spectroscopy In a rather unusual reaction, 9 reacted w ith excess cyclohexylamine to give the unsymmetrical hydrolyzed product [H( O)P(N-t-Bu)(2)(NHC6H11)] (11). A single crystal X-ray structure determinati on confirms the cis disposition of aryloxy groups in 2 as well as that of t he phosphoryl oxygen and the cyclohexylamino group in 11. (C) 1999 Elsevier Science Ltd. All rights reserved.