Facile cyanamide–ammonia coupling mediated by cis- and trans-[PtIIL2] centers and giving metal-bound guanidines

Marina R. Tyan; Nadezhda A. Bokach; Meng-Jiy Wang; Matti Haukka; Maxim L. Kuznetsov; Vadim Yu. Kukushkin

doi:10.1039/B806862C

Facile cyanamide–ammonia coupling mediated by cis- and trans-[Pt^IIL₂] centers and giving metal-bound guanidines†

Marina R. Tyan,^a Nadezhda A. Bokach,*^a Meng-Jiy Wang,^b Matti Haukka,^c Maxim L. Kuznetsov^d and Vadim Yu. Kukushkin*^ae

Author affiliations

* Corresponding authors

^a Department of Chemistry, St.Petersburg State University, 198504 Stary Petergof, Russian Federation
E-mail: bokach@nb17701.spb.edu
Fax: +7 (812) 428 6939

^b Department of Chemical Engineering, National Taiwan University of Science and Technology, 43, Keelung Road, Section 4, Taipei, 106 Taiwan

^c Department of Chemistry, University of Joensuu, P.O. Box 111, Joensuu, Finland

^d Department of Chemistry, Moscow Pedagogical State University, 3, Nesvigskiy per., 119021 Moscow, Russian Federation

^e Institute of Macromolecular Compounds of the Russian Academy of Sciences, V. O. Bolshoi Pr. 31, 199004 St.Petersburg, Russian Federation
E-mail: kukushkin@VK2100.spb.edu

Abstract

Diffusion of ammonia into CH₂Cl₂ solutions of the dialkylcyanamide complexes cis- or trans-[PtCl₂(RCN)₂] (R = NMe₂, NEt₂, NC₅H₁₀) at 20–25 °C leads to metal-mediated cyanamide–ammonia coupling to furnish, depending on reaction time, one or another type of novel bisguanidine compound, i.e. the molecular cis- or trans-[PtCl₂{NH [double bond, length as m-dash] C(NH₂)R}₂] (cis-1–3 and trans-1–3) and the cationic cis- or trans-[Pt(NH₃)₂{NHC(NH₂)R}₂](Cl)₂ (cis-4–6 and trans-4–6) complexes. Compounds cis-1–3 or trans-1–3 were converted to cis-4–6 or trans-4–6, accordingly, upon prolonged treatment with NH₃ in CH₂Cl₂. The ammination of the relevant nitrile complexes cis- or trans-[PtCl₂(RCN)₂] (R = Et, CH₂Ph, Ph) in CH₂Cl₂ solutions affords only the cationic compounds cis- or trans-[Pt(NH₃)₂{NH [double bond, length as m-dash] C(NH₂)R}₂](Cl)₂ (cis-7–9 and trans-7–9). The formulation of 1–9 was supported by satisfactory C, H and N elemental analyses, agreeable ESI⁺-MS (or FAB⁺-MS), IR, ¹H and ¹³C NMR spectroscopies. The structures of trans-1, trans-3, cis-4, trans-4, cis-7, and cis-9 were determined by single-crystal X-ray diffraction disclosing structural features and showing that the ammination gives ligated guanidines and amidines in the E- and Z-forms, respectively, where both correspond to the trans-addition of NH₃ to the nitrile species.

Supplementary files

Article information

DOI: https://doi.org/10.1039/B806862C
Article type: Paper
Submitted: 23 Apr 2008
Accepted: 18 Jun 2008
First published: 11 Aug 2008

Download Citation

Dalton Trans., 2008, 5178-5188

Permissions

Request permissions

Facile cyanamide–ammonia coupling mediated by cis- and trans-[Pt^IIL₂] centers and giving metal-bound guanidines

M. R. Tyan, N. A. Bokach, M. Wang, M. Haukka, M. L. Kuznetsov and V. Yu. Kukushkin, Dalton Trans., 2008, 5178 DOI: 10.1039/B806862C

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Dalton Transactions