Substitution reactions of dihydridotetracarbonyliron

Abstract

The i.r. [(ν(CO) and ν(Fe–H)] and Mössbauer spectra of H2Fe(CO)4 in hexane at –78 and –196° are reported. The reaction between H2Fe(CO)4 and thiols proceeds by simultaneous loss of hydrogen and carbon monoxide to the known thiolate-bridged complexes, [Fe(CO)3SR]2(R = Ph, C6F5, or Pri). With triphenyl-phosphine and -arsine, hydrogen substitution occurs producing the complexes, Fe(CO)4L and Fe(CO)3L2(L = Ph3P or Ph3As). Two unstable complexes were also isolated in low yield from the Ph3As reaction, one of which was identified by mass spectrometry as Fe(CO)4H2AsPh3. A structure with bridging hydrogen atoms between iron and arsenic is suggested.