title: Very large changes in bond length and bond angle in a heavy group 14 element alkyne analogue by modification of a remote ligand substituent.
abstract: The synthesis and characterization of the compound Me3Si-4-Ar'SnSnAr'-4-SiMe3 (Ar'-4-SiMe3 = C6H2-2,6-(C6H3-2,6-i-Pr2)2-4-SiMe3) shows that it has a Sn-Sn bond length = 3.066(1) A and a Sn-Sn-C bending angle of 99.25(14) degrees . These parameters differ by about 0.4 A and about 26 degrees from those previously reported for the closely related Ar'SnSnAr' (Ar' = C6H3-2,6-(C6H3-2,6-i-Pr2)2). The results show that, in accordance with the theoretical predictions by Nagase and Takagi, very small amounts of energy (ca. 5 kcal mol-1) separate structural isomers of distannynes that have large differences in their bonding parameters.
authors.affiliation: Department of Chemistry, University of California, Davis, One Shields Avenue, Davis, California 95616, USA.
authors.forename: Roland C
authors.initials: RC
authors.lastname: Fischer
authors.forename: Lihung
authors.initials: L
authors.lastname: Pu
authors.forename: James C
authors.initials: JC
authors.lastname: Fettinger
authors.forename: Marcin A
authors.initials: MA
authors.lastname: Brynda
authors.forename: Philip P
authors.initials: PP
authors.lastname: Power