Reductive cleavage of propellane-type hydrazinium dications as a route to medium-sized ring bicyclic diamines with bridgehead nitrogen atoms

Abstract

Procedures are described for the preparation of 1,5-diazoniatricyclo[3.3.2.0]decane (9), 1,5-diazoniatricyclo[3.3.3.0]undecane (10),1,6-diazoniatricyclo[4.3.3.0]dodecane (11),1,6-diazoniatricycol[4.4.3.0]tridecane (12), and 1,6-diazoniatricyclo[4.4.4.0]tetradecane (13) salts by the alkylation of 1,5-diazabicyclo[3.3.0]octane and 1,6-diazabicyclo[4.4.0]decane with suitable difunctional molecules X[CH₂]_mY. The central N–N bond of these propellane-type hydrazinium dications may be cleaved by a variety of reducing agents to yield the bicyclic diamines 1,5-diazabicyclo[3.3.2]decane (21), 1,5-diazabicyclo[3.3.3]undecane (22), 1,6-diazabicyclo[4.3.3]dodcecane (23), 1,6-diazabicyclo[4.4.3]tridecane (24), and 1,6-diazabicyclo[4.4.4]tetradecane (25). The scope and limitations of this synthetic route to medium-sized ring bicyclic diamines are discussed.