The reaction of CH3NH2 with SnX2, CH3NH3SnX3 (X=Cl, Br, I), and BiI3 – The first Sn(II)‐Ammine complexes as intermediates. Issue 23 (16th August 2022)

• Record Type: Journal Article
• Authors: Krummer, Michael; Daub, Michael; Hillebrecht, Harald
• Is Part Of: Zeitschrift für anorganische und allgemeine Chemie. Volume 648:Issue 23(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-08-16
• Subjects: methylamine ligand -- coordination compound -- isolated intermediates -- SnX2 -- MASnX3; Chemistry, Inorganic -- Periodicals; Chemistry -- Periodicals; 540
• DOI: 10.1002/zaac.202200147
• Languages: English
• ISSNs: 0044-2313

Abstract

Abstract: In order to understand the "molten salt approach" for CH3 NH3 PbI3, we have investigated the interaction of gaseous CH3 NH2 with Pb X 2 ( X =Cl, Br, I) and MAPb X 3 (MA=CH3 NH3 + ; X =Cl, Br, I) and characterised the first ammine complexes of Pb(II). In continuation, we have extended our work to the corresponding Sn(II) halides, i. e. Sn X 2 ( X =Cl, Br, I) and MASn X 3 ( X =Cl, Br, I). With X =iodine we have obtained cubic [Sn(CH3 NH2 )6 ]I2, which is isotypic to the lead compounds with X =I and Br showing a close similarity to the K2 PtCl6 type due to the octahedra [Sn(CH3 NH2 )6 ] 2+ . Release of CH3 NH2 yields [Sn(CH3 NH2 )4 I]I. Here, Sn 2+ is fivefold coordinated by 4 CH3 NH2 ligands and one I − as a square pyramid with the I − in an equatorial position. Charge neutrality is achieved by a second I − anion with a significant longer distance of 4.29 Å, completing the square pyramid to a distorted octahedron. With X =Br and Cl, only one compound forms, Sn(CH3 NH2 )5 Br2 and Sn(CH3 NH2 )5 Cl2, respectively. Both structures are isotypic and crystallize in an orthorhombic structure with square‐pyramidal [Sn(CH3 NH2 )5 ] 2+ units. For all representatives with mixed ligands, the interaction with X − is significantly weaker than with CH3 NH2 . H‐bridges N−H⋅⋅⋅ X contribute to the interaction between the Sn(CH3 NH2 )4 X 2 units. All compounds show high sensitivity to moisture and limited thermal stability. They decompose in air to CH3 NH3 X and a white amorphous residue, probably Sn(OH) X . The reaction of CH3 NH2 with BiI3 results in (CH3 NH3 )4 (CH3 NH2 )BiI7 according to traces of moisture. Abstract :