The x-ray structure determinations and semiempirical PM3 calculations of two chloro(piperidyl)cyclotri(phosphazenes)

✍ Scribed by Thomas M. Klapötke; Peter S. White

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 174 KB
• Volume: 8
• Category: Article
• ISSN: 1042-7163
• DOI: 10.1002/(sici)1098-1071(1997)8:3<267::aid-hc10>3.0.co;2-p

✦ Synopsis

Single crystals of 2,4,6,6-tetrachloro-2,4-bis(piperidyl)cyclotri(phosphazene) (1a) and of 2,4,6-trichloro-2,4,6-tris(piperidyl)cyclotri(phosphazene) (2a) were grown from petroleum ether solution. The structures of both compounds were determined by single-crystal X-ray diffraction analyses. Compound 1a crystallizes in the monoclinic space group P 2 1 /n with Z ‫ס‬ 4 and unit cell dimensions a ‫ס‬ 9.3994( 4), b ‫ס‬ 19.204(3), c ‫ס‬ 11.5664(4) A ˚, and b ‫ס‬ 108.718(4)Њ. Compound 2a crystallizes in the triclinic space group P with Z ‫ס‬ 4 1 and unit cell dimensions a ‫ס‬ 12.8289(2), b ‫ס‬ 13.8856(2), c ‫ס‬ 14.63810(10) A ˚, and ␣ ‫ס‬ 100.7621(5), b ‫ס‬ 91.0094(2), c ‫ס‬ 113.9757( 6)Њ. The experimentally obtained structural parameters for the covalent molecules 1a and 2a compare well with those calculated at the semiempirical PM3 level of theory. These results give credence to the PM3 calculated structures of 2,4,6,6-tetraazido-2,4-bis(piperidyl)cy-# Prior to publication the results presented in this paper were made available to the DRA (UK).