Iminocarbonyl

Riboflavin, folic acid and lumiflavin each bind one Ru(bpy)2 unit. The MLCT spectra of the complexes are pH dependent, and an a-iminocarbonyl chelating mode for each ligand is proposed. Coordination results in a lowering of the values ( 9 to 5) of the N(3)-H protons." ... 

Poly(imino-l,4-phenyleneiminoterephthaloyl) (XIV) (trade names Kevlar, Twaron) is synthesized from the corresponding para-substituted diamine and diacid chloride. Poly (iminocarbonyl-l,4-phenylene) (XV) (also known as Kevlar) is based on p-aminobenzoic acid. 

The photochemical rearrangement of enamides of carboxylic acids 20,113-116 is analogous to the photochemical rearrangement of enol esters (Section VII), except that it proceeds more efficiently and in much higher yield. It seems that the latter can be attributed to the high photochemical stability of the photoproducts. The )3-iminocarbonyl compound 187 formed immediately after the... 

The reaction step of heterocyclization of iminocarbonyl compounds 136 is probably the rate-limiting stage, as for monocyclic pyrylium salts [82AHC(Suppl)]. Its rate is determined by the electrophilicity of the carbonyl group and by steric factors. In the case of a bulky 3-aryl group, especially with donor substituents, the rate of heterocyclization should be retarded, and because of this influence, the behavior of 136 becomes dependent on the nature of R3. Thus, if R3 = Me or Et, the possibility of intramolecular aldol-type condensation is real, and a-naphthylamines 140 are formed (82KGS552). 

Early findings by Suzuki and co-workers [109] showed that the palladium-catalyzed iminocarbonylative cross-coupling reaction between 9-alkyl-9-BBN derivatives, t-butylisocyanide, and arylhalides gives access to alkyl aryl ketones 132 after hydrolysis of the corresponding ketimine intermediates 131. Presumably, the concentration of free isocyanide is kept to a minimum by its coordination with the borane. Formation of an iminoacylpalladium(II) halide 130 by insertion of isocyanide to the newly formed arylpalladium complex followed by a transmetallation step afford the ketimine intermediates 131 (Scheme 8.52). 

Based on this concept, Whitby and co-workers [110] reported an interesting palladium-catalyzed three-component synthesis of aromatic and heteroaromatic amidines 133 starting from unsaturated halides, amines, and t-butylisocyanide (Scheme 8.53). The catalytic cycle for this iminocarbonylative coupling reaction is analogous to the reactions incorporating carbon monoxide-isoelectronic with isocyanides-as the third partner [111]. 

Beim Erhitzen von Diphenyl-trichlor-phosphoran mit N-(Perfluoralkyl-iminocarbonyl)-perfluorarylamidinen auf 97-100° entstehen unter Chlorwasserstoff-Abspaltung in guter Ausbeute 4,6-Bis- [perfluoralkyl] - 2,2-diary 1-1,3,5,2k5- triazaphos pho-... 

Die Herstellung von S-(Amino-iminocarbonyl)-dithiophosphorsdure-0,0-dimethylester bzw. -0,0-diethylester (90%) erfolgt aus Thioharnstoff und den entsprechenden Thio-phosphorsaure-chlorid-O.O-diestern in Ethanol146 ... 

Loss of nitrogen and a proton shift in a-azidocarbonyl compounds upon pyrolysis gives a-iminocarbonyl compounds which condense with benzene-1,2-diamine in situ to afford 2,3-disubstituted quinoxalines. 

A series of 2-imidazolidin-2-one substituted benzothiazoles 62 are prepared from O-amidinylhydroxylamines 58 with aryl isothiocyanates 59 in moderate yields <05PJC115>. The reaction pathway has been proposed to proceed via iminocarbonyl sulfenamide 61, which undergoes spontaneous sulfurization of the aromatic ring with loss of 1-aminocyclohexanecarbonitrile to furnish benzothiazole 62. 

Poly[carbonylimino-(6-hydroxy-l,3-phenylene)-metliylene-(4-hydroxy-l,3-phenylene)iminocarbonyl-l,3-phenylene] ... 

Poly[oxy-(4-amino-l,3-phenylene)iminocarbonyl(4,9-dicarboxytricyclo[4 2.2.02 5]-7 -decane-3,10-diyl)-carbonylimino- ... 

Aroylamino-thiocarbonylamino)-1028 2-(Aryl-iminocarbonyl-amino)- 1029 2-(5-Aryl-tetrazolo)-1029 2-Benzylamino- 972 2-(4-Chloracetyl-anilino)- 874... 

The photoxygenation of the C = N in a-iminocarbonyl compounds results in C-C cleavage and the formation of mixtures of acids and esters (Scheme 60). The key intermediate in the proposed mechanism is the trioxa[2.1.0]pentane... 

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