Neutron diffraction analysis of the first stable hydride derivative of a divalent group-14 metal

摘要

A single-crystal neutron diffraction study at 20 K has revealed accurate hydride ligand positions in the first stable hydride derivative of a divalent group-14 metal,[2,6-Trip_2C_6H_3Sn(mu-H)]_2 centre dot 4C_6H_6,Trip=2,4,6-tri-isopropylphenyl [B.E.Eichler,P.P.Power,J.Am.Chem.Soc.122(2000)8785].In the solid state this dimeric complex assumes a trans C_(2h)geometry with two bridging hydrides(Sn-H 1.943(7)A,ZC-Sn-H 92.4(2)deg ,ZSn-H-Sn'106.9(3)deg ,ZH-Sn-H'73.1(3)deg ).The bulky Trip ligand serves to stabilize the Sn-H bonds.The tin atoms carry lone pairs,and,as determined previously by X-ray diffraction and reported by Eichler and Power,the tin coordination accordingly is pyramidal as evidenced by the sum of the three bond angles around tin of 257 deg .To our knowledge this is the first neutron diffraction study of a tin hydride complex to be reported.The neutron diffraction measurements were carried out using the time-of-flight Laue SCD instrument at the Argonne Intense Pulsed Neutron Source.