title: Oxidation of Pt-bound bis-hydroxylamine as a novel route to unexplored dinitrosoalkane ligated species.
abstract: The reaction of K 2[PtCl 4] and HO(H)NCMe 2CMe 2N(H)OH.H 2SO 4 ( BHA.H 2SO 4; 2) in a molar ratio 1:2 at 20-25 degrees C in water affords a mixture of [Pt(BHA) 2][PtCl 4] ( 5) and [Pt(BHA-H) 2] ( 6) ( BHA- H = anionic monodeprotonated form of BHA) which, upon heating at 80-85 degrees C for 12 h or on prolonged keeping at 20-25 degrees C for 2 weeks, is subject to a slow transformation giving [PtCl 2(BHA)] ( 7). The latter compound is also obtained from the reaction between K[PtCl 3(Me 2 SO)] and 2. The chlorination of [PtCl 2(BHA)] ( 7) in freshly distilled dry chloroform leads to the selective oxidation of one N(H)OH group yielding [PtCl 2{HO(H) NCMe 2CMe 2 N=O}] ( 13), while the chlorination in water produces the complex [PtCl 2(O= NCMe 2CMe 2 N=O)] ( 14) bearing the unexplored dinitrosoalkane species. Treatment of 14 with 2 equiv of 1,2-bis-(diphenylphosphino)ethane (dppe) in CH 2Cl 2 results in the liberation of the dinitrosoalkane ligand followed by its fast cyclization giving the alpha-dinitrone (3,3,4,4-tetramethyl-1,2-diazete-1,2-dioxide) in solution and the solid [Pt(dppe) 2](Cl) 2. The Pt (II) complexes with hydroxylamino ( intersection)oximes [PtCl 2{HO(H) NC(Me) 2C(R)= NOH}] (R = Me 8; R = Ph 9) upon their oxidation with Cl 2 in CHCl 3 afford the nitrosoalkane derivatives [PtCl 2{O= NCMe 2C(R)= NOH}] (R = Me 16; Ph 17), respectively, while the corresponding chlorination of the bis-chelates [Pt{HO(H) NCMe 2C(R)= NOH} 2] (R = Me 10; Ph 11) gives [Pt{O= NCMe 2C(R)= NO} 2] (R = Me 18; Ph 19). The formulation of 5- 19 is based on C, H, and N microanalyses, IR, 1D ( (1)H, (13)C{ (1)H}, (195)Pt) and 2D ( (1)H, (1)H-COSY, (1)H, (13)C-HSQC) NMR spectroscopies, and X-ray diffraction for five complexes ( 5, 7, and 12- 14).
authors.affiliation: Centro de Química Estrutural, Complexo I, Instituto Superior Técnico, TU Lisbon, Av. Rovisco Pais, 1049-001 Lisbon, Portugal.
authors.forename: Konstantin V
authors.initials: KV
authors.lastname: Luzyanin
authors.forename: Pavel V
authors.initials: PV
authors.lastname: Gushchin
authors.forename: Armando J L
authors.initials: AJ
authors.lastname: Pombeiro
authors.forename: Matti
authors.initials: M
authors.lastname: Haukka
authors.forename: Victor I
authors.initials: VI
authors.lastname: Ovcharenko
authors.forename: Vadim Yu
authors.initials: VY
authors.lastname: Kukushkin
mesh_terms: D000473:Alkanes / Q000737:chemistry*; D002614:Chelating Agents / Q000737:chemistry; D019811:Hydroxylamine / Q000737:chemistry*; D008024:Ligands; D009603:Nitroso Compounds / Q000737:chemistry*; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D010084:Oxidation-Reduction; D010984:Platinum / Q000737:chemistry*
chemical_list: D000473:Alkanes; D002614:Chelating Agents; D008024:Ligands; D009603:Nitroso Compounds; D009942:Organometallic Compounds; D019811:Hydroxylamine; D010984:Platinum