New Nitrosylrhenium Hydrides as Precursors of “Diazo” Complexes: Preparation of Hydrazine and Diazene Derivatives

Abstract

] to react first with triflic acid and then with hydrazine. The complexes were characterized spectroscopically and by the X-ray crystal structure determination of [Re(OC 2 H 5 )(NH 2 NH 2 )(NO){PPh(OEt) 2 } 3 ]-BPh 4 (5a). Oxidation of the hydrazine complexes 4−6 was studied with Pb(OAc) 4 at −30°C and, depending on the na-

Reactions of Azides Coordinated to Ruthenium(II) Centers with Haloalkanes To Afford Nitrogen‐Containing Moieties

“…The structural parameters, as shown in Table , related to the imine moiety are similar to those of previously reported methyleneimine complexes, [18b] and the ethylideneimine complex [Ru(NH=CHCH 3 )(PPh 3 )(CN t Bu)(Tp)] (Tp = trispyrazolylborate) synthesized in a similar manner . Owing to the N1–C1 bond lengths of the imine moiety [1.146(6) Å for 2b and 1.279(3) Å for 5b ], these bonds were considered to be double bonds; the bond length of 2b was shorter and that of 5b was longer than those of other imine ligands (1.202–1.272 Å) ,.…”

“…Owing to the N1–C1 bond lengths of the imine moiety [1.146(6) Å for 2b and 1.279(3) Å for 5b ], these bonds were considered to be double bonds; the bond length of 2b was shorter and that of 5b was longer than those of other imine ligands (1.202–1.272 Å) ,. [18b], The N1–C1–C2 bond angles of the imine moiety [140.9(5)° for 2b and 129.00(10)° for 5b ] were consistent with the expected angles for sp 2 ‐hybridized nitrogen atoms.…”

“…Methyleneimine (NH=CH 2 ) is an unstable compound and has only been observed through low‐temperature IR absorption spectroscopy . An alternative synthesis of a methyleneimine complex through the oxidation of a methylhydrazine ligand bound to a rhenium(I) center in [Re I (NH 2 NHCH 3 )(CO){P(OEt) 3 } 4 ] + has also been reported . The hydrogenation of the methylimido ligand of the osmium complex [Os(NCH 3 ){CH 2 Si(CH 3 ) 3 } 2 (η 5 ‐C 5 H 5 )] + affords a methyleneimine moiety in a κ 2 N , C coordination mode .…”

Formation of a Methyleneimine Moiety by Reaction of a RuII‐Coordinated Azide Ion with Methyl Iodide

“…A few metal complexes containing a methyleneimine moiety (NHCH 2 ) have been synthesized by the reaction of a methylhydrazine or methylimido complex 10. The NHCH 2 ligand coordinates through two coordination modes; one is the N‐monodentate mode ( κN ) of a rhenium complex10a–c and another the N , C ‐bidentate one ( κ 2 N , C ) of an osmium complex 10d. Only one rhenium complex containing an methyleneimine‐ κN moiety has been characterized by X‐ray crystallography 10c.…”

Preparation of Cyanoguanidine and Ethylcyanamide Complexes of Ruthenium(II) and Osmium(II)

“…Instead, only one report is known for ruthenium [11] and none for osmium. We are interested in the chemistry of "diazo" and "triazo" complexes of transition metals with d 6 configuration and have reported the synthesis not only of diazene and hydrazine derivatives [12] but also of amidrazone complexes obtained by nucleophilic attack of hydrazine on coordinated nitrile. [13] We have now extended these studies to cyanamide, and this paper reports the preparation of cyanoguanidine and diethylcyanamide complexes of ruthenium and osmium stabilised by half-sandwich p-cymene fragments.…”