Elimination complexes

Combination of circulating antigens and antibodies to form immime complexes is a normal phenomenon, and normally this immune complex eliminates by... 

Kaupp, G. Complex Eliminations Eliminations with Rearrangements. 146, 57-98 (1988). 

Reversible pyridine dissociation yields the non-Lewis base stabilized imido complex [Cp(NHAr) Ti=NAr] (54). This coordinatively unsaturated species undergoes a [2 + 2] cycloaddition reaction with allene to give an azatitanocyclobutane (55), which is then protonated to the /mamido complex. Elimination of enamine occurs followed by isomerization to the energetically more favorable imine. 

The corresponding complex 67 is formed using complex 6 [2h]. With the aldimine MeN=CHPh and complex 2a, a similar complex eliminates methane with the formation of complex 68 [3a]. 

The entire photolysis sequence can be reversed readily by H2, as summarized in Scheme 1 (27). A sealed, degassed benzene solution of [IrClH2(PPh3)3], from which the photoreleased H3 is not allowed to escape, can be cycled repeatedly (>50 cycles) through the photoinduced H2 elimination-thermal H2 addition reactions without any observable loss of complex. Elimination of H2 can be induced by irradiation with X < 400 nm. The quantum yield of elimination, measured at 254 nm by monitoring the growth of the 449-nm band of [IrCl(PPh3)3], is 0.56 0.03. 

Keywords benzothiazepinone, [l,5,5, (4)5]-elimination, ring contraction, complex elimination, benzothiazole... 

Keywords quinolizine, complex elimination, ring contraction, indolizine... 

If the initial organopalladium complex is formed in the presence of an alkene, transfer of the organyl group to the alkene can occur (Heck reaction, Scheme 8.7) [5, 78], Electron-deficient and electron-rich alkenes and even some arenes [79] can be used. In the last step of this process a Pd-hydrido complex is formed by /3-hydride elimination, leading to the formation of the C-C double bond. In the presence of bases the hydrido complex eliminates HX, regenerating the catalytically active Pd(0) complex (Scheme 8.7). 

Cyclic 1,3-diene iron tricarbonyl complexes eliminate hydrogen on electron impact to give predominant odd electron ions with iron bonded to an aromatic system 57) These same molecules eliminate hydrogen and iron on photolysis to give aromatic hydrocarbon products. 

Complex Elimination with One Migrating Group (Bond).62... 

Complex Eliminations with Two Migrating Groups (Bonds).82... 

Complex Eliminations with More Than Two Migrating Groups.89... 

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