770-92-3Relevant academic research and scientific papers
Pyrolysis of Three Acetates of Methylbicycloheptan-2-ols and the Parent Alcohols
Vainiotalo, Pirjo,Pohjala, Esko,Maelkoenen, Pentti
, p. 1537 - 1540 (2007/10/02)
The acetates of exo-2-methyl-endo-bicycloheptan-2-ol, endo-2-methyl-exo-bicycloheptan-2-ol, and 1-methyl-exo-bicycloheptan-2-ol together the parent alcohols have been pyrolysed at several temperatures and the product distribution determined.The mechanism and direction of elimination in relation to structure are discussed qualitatively.The formation of the principal products is consistent with a concerted elimination involving a six-membered cyclic transition state.Wagner-Meerwein rearrangement occurs as a competing reaction in cases where the formation of a tertiary structure is possible at the expense of a secondary one.In the case studied a two-step reaction is considerably faster than direct pyrolysis of the secondary structure.
Deamination Reactions, 39. Decomposition of 1-Methylnorbornane-2-diazonium Ions
Banert, Klaus,Kirmse, Wolfgang,Wroblowsky, Heinz-Juergen
, p. 3591 - 3610 (2007/10/02)
Nitrous acid deaminations of 1-methyl-exo-2-norbornylamine (19) and of the epimeric 2-methyl-2-norbornylamines (32, 34) in water yielded endo-2-methyl-exo-2-norbornanol (42a) exclusively.In contrast, 1-methyl-endo-2-norbornylamine (23) afforded 2-methylbicycloheptan-2-ol (13a, 20percent) and 1-methyl-endo-2-norbornanol (14a, 17percent) in addition to 42a.The formation of bicycloheptyl derivatives 13 is accentuated by better nucleophiles, as shown by photolyses of 1-methyl-2-norbornanone tosylhydrazone (35) in methanol/methoxide, and in the presence of lithium azide. 14 and (in part) 13 are thought to originate from 7-bridged 1-methylnorbornyl cations (10).A substantial fraction of 13 stems from the open 2-methylbicycloheptyl cation (12).The contributions of 10 and 12 have been elucidated by means of 3-D2 labels.Introduction of an exo-3-methyl group (48, 50) enhances participation of the C-1 - C-7 bond.Cations 57 and 61 are the predominant intermediates generated from 1,exo-3-dimethylnorbornane-endo-2-diazonium ions (53).Less polar solvents (acetic acid, 2-ethylhexanoic acid) induce variations in product distribution which are attributed to increasing solvolytic displacement (ks) and ion pair collapse.
Norpinyl-Norbornyl Rearrangements: 2-Methyl- and 2,exo-6-Dimethylbicycloheptane Derivatives
Banert, Klaus,Kirmse, Wolfgang,Wroblowsky, Heinz-Juergen
, p. 2474 - 2485 (2007/10/02)
Solvolyses of 2-methylbicyclohept-2-yl-4-nitrobenzoate (9), the nitrous acid deamination of the corresponding amine (4e), and acid-catalyzed rearrangements of various 2-methylbicycloheptane derivatives (4a - c) have been investigated. 2-Methylbicycloheptyl (4) and 1-methyl-endo-2-norbornyl (10) products prevailed; minor quantities of 2-methyl-exo-2-norbornyl derivatives (12) were also obtained.The product distributions were independent of the precursor but were strongly affected by the nucleophilicity of the solvent.Our observations are consistent with the 7-bridged norbornyl cation 6 as the predominant intermediate.Further stabilization of 6 by exo-3-methyl substitution is indicated by the results of the acid-catalyzed rearrangement of 2,exo-6-dimethylbicycloheptan-2-ol (17).
