Reactions of aziridine, thiirane, and oxirane with isocyanide ligands in complexes of palladium(II) and platinum(II): syntheses of neutral five-membered cyclic diamino-, aminothio-, and aminooxycarbene compounds

Abstract

ChemInform Abstract The complexes (I) react with aziridine (II) to give the diaminocarbene complexes (III). In the case of (IV) depending on the nature of the RNC ligand, one or two of the ligands are converted to carbene groups. The formation of (VI) proceeds via the mixed carbene-isocyanide complex. Thiirane (VII) reacts similarly to (II) with (I) or (IV) to give the compounds (VIII). It does not react with the bulky tBuNC ligand in (Ia). In contrast to the reactions of (II) and (VII), oxirane (IX) alone fails to convert the isocyanide ligand in the Pd and Pt complexes to a cyclic aminooxycarbene ligand. In the presence of NaCl a slow conversion of Pt complexes leads to (X). Similar reactions with Pd-CNR derivatives do not give any aminooxycarbene compounds. The proposed reaction mechanisms for the cyclization reactions of the coordinated RNC ligands by the heterocycles as well as the IR, 1H and 31P NMR spectra of the cyclic carbene products are discussed.

Semibullvalene and Diazasemibullvalene: Recent Advances in the Synthesis, Reaction Chemistry, and Synthetic Applications

“…By comparison, cycloadditions of isocyanides, azides, diazo compounds, and nitroso compounds with standard aziridines are all very rare. 27,28 The cycloaddition reactions of NSBVs with different substrates require different Lewis acid catalysts to achieve the best yields. The most efficient catalysts for cycloaddition of NSBVs with isocyanides, azides, and diazo compounds are Zn(OTf) 2 , La(OTf) 3 , and Sc(OTf) 3 , respectively.…”

Novel Palladium–Aminocarbene Species Derived from Metal-Mediated Coupling of Isonitriles and 1,3-Diiminoisoindoline: Synthesis and Catalytic Application in Suzuki–Miyaura Cross-Coupling

“…This complex was prepared using a modified procedure previously employed for the preparation of cis-[PdCl 2 (CNR 1 ) 2 ] (R 1 = Cy 1, Bu t 2, Xyl 3). 49 Reaction of 1 with 1,3-Diiminoisoindoline (9). Solid 1,3-diiminoisoindoline (0.029 g, 0.20 mmol) was added to a solution of cis-[PdCl 2 (CNCy) 2 ] (0.040 g, 0.10 mmol) in CHCl 3 (10 mL), and the reaction mixture was refluxed for 4 h. During this period, the color of the mixture gradually turned from light yellow to orange followed by precipitation of a yellowish-orange solid.…”

β‐Protic Pyrazole and N‐Heterocyclic Carbene Complexes: Synthesis, Properties, and Metal–Ligand Cooperative Bifunctional Catalysis

“…[48,49] The reactions of the isocyanide complexes 42 with a-aminoacetals result in the formation of the protic NHC complexes 43 as shown in Scheme 17. [50,51] Other functionalized amines such as w-halo-A C H T U N G T R E N N U N G alkylamines [52] and aziridine [53,54] are also used as the nucleophile to afford protic NHC complexes. Ruiz and co-workers reported coupling of isocyanide ligands in 44 and propargylamine giving the protic NHC complex 45 (Scheme 18), [55,56] while Fehlhammer and co-workers synthesized a series of protic NHC complexes 48 through Ugi-type four-component condensation reactions involving protonated cyano complexes, as depicted in Scheme 19.…”