Computational Modeling of the Feasibility of Substituted [1.1.1]Propellane Formation from Anionic Bridgehead Bromide Precursors

[1.1.1]Propellane, a compound whose structure includes two saturated carbons in which all four bonds are directed into single hemisphere, is of theoretical interest, but has also seen recent practical applications. Mono-, di-, and trisubstituted derivatives this propellane (by substitution its CH2 bridges with O, S, NH, CF2, CO, SO, SO2) remain unknown despite several computational studies that have suggested some may be stable. In study, we show that, cases, substituted propellanes spontaneously formed upon the attempted optimization geometries anionic bridgehead bromide precursors using ωB97X-D/aug-cc-pVDZ DFT method. Spontaneous formation suggests these at lower energy relative to and, therefore, promising synthetic targets. The success or failure form considered relation length strain central bridgehead-bridgehead bond, as well total each propellane.