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A suspension of the o -quinone monoimide 1,2-N(C(O)-4-C 6 H 4 NO 2 )O-2,4-C 6 H 4 Cl 2 and IrCl(CO)PPh 3 ) 2 in CH 2 Cl 2 was stirred for 3 days at room temperature. After careful chromatography two compounds were isolated, both with the empirical formula Ir(1,2-N(C(O)-4C 6 H 4 NO 2 )O-2,4-C 6 H 2 Cl 2 )Cl(CO)(PPh 3 ) 2 . These were shown by 1 H, 13 C and 31 P NMR and IR spectroscopy to be two of the twelve geometrical isomers possible for this complex. X-Ray crystallography confirmed these structures and showed that one isomer has cis and the other trans triphenylphosphine ligands.

Le traitement de l'o-quinone monoimide N-(2,4-dichloro-6-oxo-2,4-cyclohexadien-1-ylidene)-4-nitrobenzamide (I) avec les 2,6-dimethyl- et 2,6-dichlorophenols donne des composes d'addition formes par attaque nucleotide du phenol sur l'azote imido de I. Certains de ces composes d'addition peuvent etre ensuite oxydes par I ou par la DDQ pour conduire a la N-aryl-p-iminoquinone selon une nouvelle migration acyle N→O

o-Quinone monoimides undergo inverse electron demand Diels-Alder reactions with thiophene, 2-alkylated thiophenes, 2-and 2,5-alkylated furans and benzofurans. 2,5-Dimethylthiophenes and 2-methylbenzo[b]thiophene, on the other hand interact with o-quinone monoimides to yield ethers, products arising from hydride abstractions from the methyl groups by the imido nitrogen of 6

Reaction of the o-quinone monoimide (I) with electron-rich (hetero)aromatic reagents such as (II), (IV), (VI), and (VIII) yields the products (III), (V), (VII), and (IX).

The reactions of N-(2,4-dichloro-6-oxo-2,4-cyclohexadien-1-ylidene)-4-nitrobenzamide ( 1 ) with various conjugated dienes have been studied. The heterodiene system of 1 reacts with one of the double bonds of E-1, 3-pentadiene, E,E-2,4-hexadiene, E,E-1,4-diphenyl-1,3-butadiene, E,E-2,4-hexadienal, ethyl sorbate, 1-methoxy-1,3-butadiene, cyclopentadiene, 1,2,3,4-tetra-phenylcyclopentadiene in an inverse electron-demand Diels-Alder reaction to give derivatives of 2,3-dihydro-1,4-benzoxazines. In contrast to the above dienes 1,3-butadiene adds across the N-acylimino group of 1 to give the spiro adduct 2b .

Derivatives of aziridine or ethylenimine are isomerized by acids, nucleophilic reagents, or pyrolysis. All of the isomerizations reported so far are ring-opening reactions, predominantly involving cleavage of the carbon-nitrogen bond of the ring, although a few isomerizations are known in which the carbon-carbon bond of the ring is broken. Isomerization of appropriate aziridine derivatives provides useful synthetic pathways leading to heterocyclic systems such as oxazolines, imidazolines (and related systems), imidazolidinoes, thiazolines, pyrazolines, and triazolines. Other isomerizations form N-unsaturated amides, anils, and isocyanates.

Derivate des Aziridins (Athylenimins) werden durch Sauren, nucleophile Reagentien oder bei der Pyrolyse isomerisiert. Alle bis heute bekannten Umlagerungen verlaufen unter Ringoffnung, wobei vor allem die Bindung zwischen Kohlenstoff und Stickstoff gespalten wird. In wenigen Fallen offnet sich der Ring zwischen den beiden Kohlenstoffatomen. Die Umlagerungen sind praparativ brauchbare Verfahren zur Herstellung heterocyclischer Verbindungen (Oxazoline, Imidazoline und verwandter Substanzen, Imidazolidinone, Thiazoline, Pyrazoline, Triazoline). Auch N-ungesattigte Amide sowie Anile und Isocyanate lassen sich aus Aziridinen gewinnen.

Diaziridine (I) reagieren mit Dibenzoylacetylen (II) unter Ringspaltung zu den Butendionen (III), die unabhangig aus den Hydrazonen (IV) erhalten werden.