An extraction of ‘K2GeAs’ in 1,2-diaminoethane/4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane (en/crypt-222) affords As4-type pseudo-tetrahedral anions (Ge2As2)2−, (Ge3As)3−, and (GeAs3)−. On reaction with [MR2], up to four (Ge2As2)2− or...