β-Cyanoethyl Anion:  Lusus Naturae Grant N. Merrill Gregg D. Dahlke Steven R. Kass 10.1021/ja953796o.s001 https://acs.figshare.com/articles/dataset/_-Cyanoethyl_Anion_Lusus_Naturae/3658719 A stable E1<sub>cb</sub> intermediate, β-cyanoethyl anion (<b>1</b>β), has been synthesized in the gas phase at room temperature under thermal conditions via the fluoride-induced desilylation of 3-(trimethylsilyl)propionitrile. The reactivity and thermodynamic properties of this ion are reported. The cyano group is found to lower the proton affinity of <b>1</b>β by 29 ± 6 kcal/mol, which represents a particularly large substituent effect. High-level ab initio and density functional calculations have been carried out on <b>1</b>β and several related species. The computational results are compared to each other, and their accuracy is evaluated. 1996-05-08 00:00:00 ab calculation proton Cyanoethyl species desilylation density 1 β reactivity affinity cyanoethyl cyano accuracy Anion initio Naturae ion trimethylsilyl phase substituent anion Lusu E 1 cb kcal