Rert-Butyl isocyanide

NCiOjCioH, Chromium, (rert-butyl isocyanide)pentacarbonyl-, 28 143... 

MoN3C,gH27, Molybdenum, tiis(rert-butyl isocyanide)tricaibonyl-,ySic-,... 

N4NiC2oH36, Nickel(O), tetrakis(rert-butyl isocyanide)-, 28 99... 

Reaction with Isocyanides. Treatment of the reagent with rert-butyl isocyanide affords an intermediate of the nature indicated (eq 1). Subsequent reaction with a carboxylic acid at —40 °C gives an equilibrium mixture of compounds (eq 2) in which the carbonyl group is activated toward nucleophilic substitution. This intermediate can be effectively utilized in two ways. 

The unusual complex tetrakis(tert-butyl isocyanide)di-/i-chloro-di palladium(I) chlorobenzene has been prepared by Otsuka et al The preparation utilized a novel coupling reaction between bis(rert-butyl isocyanide)palladium(O) and cis-bis(rert-butyl isocyanide)dichloro-palladium(II) in cold chlorobenzene. Although the reported yield for the final step of this synthesis was good (70%), the preparation of the precursor bis(tert butyl isocyanide)palladium(O) from (i7 -allylX> cyclopenta-dienyl)palladium is time-consuming and is accomplished in only S0% yield. We have developed a greatly improved preparation of the title complex (chlorobenzene-free), which utilizes readily available Pd(0) and Pd(II) compounds as starting materials, namely bis(dibenzylideneacetone)palladium(0), [Pd(dba)2], and trans-bis(benzonitrile)dichloropalladium(II). In addition, since full details of the preparation of Pd(dba)2 have not been reported, we give a complete account of the preparation here.H... 

OjMoNCioH, Molybdenum, (fert-butyl isocyanide)pentacarbonyl-, 28 143 OjNWCigH, Tungsten, (rert-butyl iso-cyanide)pentacarbonyl-, 28 143 0,N2 VC H , Tungsten, tetracarbonyl((di-ethylamino)methylidyne](isocyanato)-, trans-, 26 42... 

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