38102-34-0Relevant articles and documents
Norpinyl-Norbornyl Rearrangements: Bicycloheptane, 4-Methyl- and 6-Methylbicycloheptane Derivatives
Kirmse, Wolfgang,Siegfried, Rainer,Wroblowsky, Heinz-Juergen
, p. 1880 - 1896 (2007/10/02)
Norpinyl-norbornyl rearrangements have been induced by solvolysis of the 2-norpinyl nitrobenzoates 15b, c and by decomposition of norpinane-, 4-methylnorpinane-, and 6-methylnorpinane-2-diazonium ions (19, 49, 64, 65).No fragmentation to monocyclic cations was observed.The yield of norpinyl products was minimal in water (s processes).With 64 and 65, migration of the bridge trans to the leaving group predominated strongly.The rearrangements afforded exo-2- and endo-2-norbornyl products in comparable quantities.The exo/endo rates depended on the nucleophilicity of the solvent but were little effected by methyl substitution at the migrating carbon.We propose the 7-bridged norbornyl cation (21) as the endo-selective intermediate which rearranges to the exo-selective 6-bridged (or rapidly equilibrating) norbornyl cation (22, 23) in competition with solvent capture.Ion-pair collapse (cf. 15b) accentuates the endo-selectivity.However, ion pairing cannot be the only source of endo-2-norbornyl products, as shown by the deamination reactions in water.
Deamination Reactions. 35. Decomposition of 5-Norbornene-2-diazonium Ions. Derivatives of Bicyclohept-2-ene
Kirmse, Wolfgang,Knoepfel, Norbert,Loosen, Karin,Siegfried, Rainer,Wroblowsky, Heinz-Juergen
, p. 1187 - 1191 (2007/10/02)
Photolysis of 5-norbornen-2-one tosylhydrazone (4) in aqueous sodium hydroxide afforded 4percent of 3-norpinen-2-ol (3) in addition to 5-norbornen-2-ol (5, 10percent) and nortricyclanol (6, 86percent). 3 arises from 5-norbornene-2endo-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-OCH3.The deamination of 1-methoxy-5-norbornen-2endo-amine (14) produced 10percent of 12, as compared to 5.6percent of 3 from 1.