ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Mercury(II) complexes of new bidentate phosphorus ylides: synthesis, spectra and crystal structures

Seyyed Javad Sabounchei, Mohammad Panahimehr, Hamid Reza Khavasi, Fateme Akhlaghi Bagherjeri, and Collete Boscovic

Faculty of Chemistry, Bu-Ali Sina University, Hamedan, 65174, Iran

Abstract: The reaction of dppm (1,1-bis(diphenylphosphino)methane) with 2-bromo-4-phenylacetophenone and benzyl bromoacetate in chloroform produces new phosphonium salts, [Ph₂PCH₂PPh₂CH₂C(O) C₆H₄Ph]Br (I) and [Ph₂PCH₂PPh₂CH₂COOCH₂Ph]Br (II). By allowing the phosphonium salts to react with the appropriate base, the bidentate phosphorus ylides, Ph₂PCH₂PPh₂=C(H)C(O)C₆H₄Ph (III) and Ph₂PCH₂PPh₂=C(H)C(O)OCH₂Ph (IV), were obtained. The reaction of these ligands with mercury(II) halides in dry methanol led to the formation of the mononuclear complexes {HgX₂[(Ph₂PCH₂PPh₂C(H)C(O)C₆H₄Ph)]} (X = Cl (V); X = Br (VI); X = I (VII)) and {HgX₂[(Ph₂PCH₂PPh₂C(H)COOCH₂Ph)]} (X = Cl (VIII); X = Br (IX); X = I (X)). The FTIR and ¹H, ³¹P and ¹³C NMR spectra were studied. The structure of compound III was unequivocally determined by the single-crystal X-ray diffraction technique. Single-crystal X-ray analysis of the {HgBr₂[(Ph₂PCH₂PPh₂C(H)C(O)C₆H₄Me)]} complex (XI) revealed the presence of a mononuclear complex containing the Hg atom in a distorted tetrahedral environment. In all complexes, the ylides referred to above were coordinated through the ylidic carbon and the phosphine atom.

Keywords: unsymmetrical phosphorus ylides – Hg(II) complexes – X-ray crystal structure

Full paper is available at www.springerlink.com.

DOI: 10.2478/s11696-013-0487-5

Chemical Papers 68 (5) 624–632 (2014)