Desaminierungsreaktionen, 35. Zerfall von 5‐Norbornen‐2‐diazonium‐Ionen. Derivate des Bicyclo[3.1.1]hept‐2‐ens

Abstract

Deamination Reactions, 35. Decomposition of 5‐Norbornene‐2‐diazonium Ions. Derivatives of Bicyclo[3.1.1]hept‐2‐ene Photolysis of 5‐norbornen‐2‐one tosylhydrazone ( 4 ) in aqueous sodium hydroxide afforded 4% of 3‐norpinen‐2‐ol ( 3 ) in addition to 5‐norbornen‐2‐ol ( 5 , 10%) and nortricyclanol ( 6 , 86%). 3 arises from 5‐norbornene‐2‐ endo ‐diazonium ions ( 2 ) as shown by the nitrous acid deamination of the epimeric amines 1 and 7 . 3‐Norpinen‐2‐one ( 12 ) was isolated by oxidation of the deamination products followed by preparative g.l.c. 3 and 12 were synthesized independently from norpinan‐2‐one ( 9 ) via sulfenylation and sulfoxide pyrolysis. The norbornene→norpinene rearrangement is slightly enhanced by 1‐OCH 3 . The deamination of 1‐methoxy‐5‐norbornen‐2‐ endo ‐amine ( 14 ) produced 10% of 12 , as compared to 5.6% of 3 from 1 .