Organobismuth compounds with the pincer ligand 2,6-(Me2NCH2)2C6H3: Monoorganobismuth(iii) carbonate, sulfate, nitrate, and a diorganobismuthenium(iii) saltElectronic supplementary information (ESI) available: X-ray crystallographic data in CIF format for 2·0.5CH2Cl2, 3, 4·H2O and 6; figures representing the optical isomers as well as the supramolecular architectures in the crystals of compounds 2·0.5CH2Cl2 and 3. CCDC reference numbers 773767 (2·0.5CH2Cl2), 773765 (3), 773764 (4·H2O) and 773766

The reaction of RBiCl 2 ( 1 ) [R = 2,6-(Me 2 NCH 2 ) 2 C 6 H 3 ] with Na 2 CO 3 or Ag 2 SO 4 (1 : 1 molar ratio) gave RBiCO 3 ( 2 ) and RBiSO 4 ( 3 ), respectively. RBi(NO 3 ) 2 ( 4 ) was obtained from RBiCl 2 and AgNO 3 (1 : 2 molar ratio). The ionic complex [R 2 Bi][W(CO) 5 Cl] ( 6 ) was obtained from R 2 BiCl ( 5 ) and W(CO) 5 (THF), following an unusual chlorine transfer from bismuth to tungsten. Compounds 2-4 are partially soluble in water. The molecular structures of 2 ·0.5CH 2 Cl 2 , 3 , 4 ·H 2 O and 6 were established by single-crystal X-ray diffraction. The carbonate 2 and the sulfate 3 exhibit a polymeric structure based on bridging oxo anions, while for the compound 4 dimer associations are formed, with both bridging and terminal nitrate anions. Dimer associations, based on weak Cl H interactions between the cation and the anion, were found in the crystal of 6 . RBiCO 3 ( 2 ), RBiSO 4 ( 3 ) and RBi(NO 3 ) 2 ( 4 ), containing the "pincer" 2,6-(Me 2 NCH 2 ) 2 C 6 H 3 ligand, exhibit chain polymeric ( 2 , 3 ) or monomeric ( 4 ) structures in solid state. Two such "pincer" ligands stabilize a bismuthenium(III) cation in [R 2 Bi][W(CO) 5 Cl] ( 6 ).