MECHANISTIC CHARACTERIZATION OF THE INTERMEDIATES IN THE THERMAL AND PHOTOCHEMICAL DEAZETATION OF 2 ISOMERIC METHYLENEPYRAZOLINES, 7-ISOPROPYLIDENE-2,3-DIAZABICYCLO[2.2.1]HEPT-2-ENE AND 2,2-DIMETHYL-3,4-DIAZABICYCLO[3.3.0]OCTA-3,8-DIENE - AN APPROACH TO THE GENERATION AND CAPTURE OF PROTOPLANAR AND PROTOBISECTED TRIMETHYLENEMETHANESO[