ASYMMETRIC NITROGEN .77. MOLECULAR-STRUCTURE OF HYL-1-((S)-1'-TOSYLPROLYL)-1,2-DIAZACYCLOHEX-2-ENE

The molecular structure of thyl-1-((S)1'-tosylprolyl)1,2-diazacyclohex -2-ene, the product of the reaction of 5-methyl-1,6-diazabicyclo[3.1.0 ]hexane with (S)-N-tosylproline chloride, has been established by X-ra y structural analysis. The pyrrolidine cycle has a half-chair conforma tion with the pyramidal nitrogen atom; the tosyl and pseudo axial carb amoyl groups have trans orientations. The diazacyclohexene cycle has a n envelope conformation with folding along the C(7)...C(9) line. The s tereochemistry of the transition state of the above-mentioned reaction is discussed.