Präparative und ir-spektroskopische untersuchungen über die zweikernigen dinatrium-dekacarbonyl-dimetallate(-I), Na 2[M 2(CO) 10], des chroms (M=Cr), molybdäns (M=Mo) und wolframs (M=W)

Abstract

Following a new method very pure sodium salts Na 2[M 2(CO) 10] (M=Cr, Mo, W) are obtained by reduction of the group VI metal carbonyls with an excess of sodium and catalytic amounts of 2,2′-bipyridine. The IR spectra of these compounds are recorded in CH 3CN (in the range of 4000-200 cm −1) and are discussed. According to these results the anions [M 2(CO) 10 2− have D 4 d symmetery and no bridging carbonyl groups. 1H-NMR investigations exclude the presence of hydrogen-bridged complexes.