REACTION OF KSI WITH M(CO)6 (M = CR, MO, W) AND CR(CO)5NME3 - CRYSTAL-STRUCTURE OF [K(DME)2]2[CR2(CO)10] (DME = 1,2-DIMETHOXYETHANE)

M(CO)6 (M = Cr, Mo, W) and Cr(CO)5NMe3 are reduced by KSi in DME during several days with formation of the anions [M2(CO)10]2-. These can be obtained from a DME/toluene solution as pale yellow or orange crystals of [K(DME)2][M2(CO)10] [M = Cr (1), Mo (2), W (3)]. A crystal structure determination of the chromium compound shows that strong interactions between the [Cr2(CO)10]2- and the K+ ions exist in the solid state, leading to the formation of one-dimensional polymeric chains. 2 and 3 are isomorphous to 1 (powder diffraction, Rietveld method).