Syntheses of chiral phosphazenes with stereogenic centers: NMR behavior in the presence of a chiral solvating agent


Asmafiliz N.

Heteroatom Chemistry, vol.25, no.2, pp.83-94, 2014 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 25 Issue: 2
  • Publication Date: 2014
  • Doi Number: 10.1002/hc.21139
  • Journal Name: Heteroatom Chemistry
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.83-94
  • Ankara University Affiliated: Yes

Abstract

The condensation reactions of tetrachloro mono (1 and 2) and bisferrocenyl spirocyclotriphosphazenes (3-5) with morpholine in tetrahydrofuran gave the partly morpholino-substituted ferrocenylphosphazenes. When the reactions were carried out with equal amounts of 1-5 and morpholine, the mono-substituted ferrocenylphosphazenes (1a, 3a-5a) formed as the major product. While the reactions were made with 1 equiv of 1-5 and 2 equiv of morpholine, the corresponding geminal-phosphazenes (1b-5b) were isolated. In addition, the condensation reactions of 1 equiv of 1-5 and 3 equiv of morpholine resulted in the formation of di-(1b-5b), tri-(2c-5c), and tetra-substituted phosphazenes. The tri-substituted compounds were isolated as major products. Some new phosphazenes have stereogenic P center(s). The stereogenic properties of 1a and 2c were investigated using 31P nuclear magnetic resonance (NMR) spectroscopy in the presence of the chiral solvating agent; (S)-(+)-2,2,2- trifluoro-1-(9′-anthryl)ethanol. The structures of all the phosphazenes were characterized by one-dimensional 1H, 13C, and 31P NMR, and two-dimensional heteronuclear single quantum coherence spectral data. The salient spectral properties of the phosphazenes were presented. © 2014 Wiley Periodicals, Inc.