133161-79-2Relevant academic research and scientific papers
Stereochemical Course of the Base-Promoted Aldol Self-Coupling of Racemic 5-Norbornen-2-one and 2-Norbornanone
Paquette, Leo A.,Moorhoff, Cornelis M.,Maynard, George D.,Hickey, Eugene R.,Rogers, Robin D.
, p. 2449 - 2455 (1991)
The enolate anions of 5-norbornen-2-one and 2-norbornanone enter into self-coupling with their conjugate acids in a manner that exhibits diastereomeric discrimination.The major products obtained from aldol reactions conducted at low temperature are those where bonding has occurred preferentially to the ketone of like absolute configuration.Structural assignments rest on X-ray crystallographic analyses and chemical interconversions.When the reactions are effected at higher temperatures, dehydration also occurs spontaneously.All indicators point to adherence by thesebicyclic systems to molecular recognition in these condensation reactions as well.The aldol products, which are stable to the conditions under which they are formed, have been evaluated for their inherent levels of total energy and strain energy by molecular mechanics methods.These data, when taken in conjunction with assumed reaction trajectories, suggest the possible causes that underlie this interesting selectivity.
Stereoselectivity of C(3) methylation and aldol condensation of camphor and derivatives
Hutchinson, J. H.,Li, D. L. F.,Money, T.,Palme, M.,Agharahimi, M. R.,Albizati, K. F.
, p. 558 - 566 (2007/10/02)
The stereoselectivity of methylation and aldol condensation of camphor and derivatives is determined by the presence or absence of a C(7) syn-methyl group and (or) C(5) and C(6) endo-hydrogen atoms.
Unsymmetrical Oxidative Cleavage of Cyclic Ketones. Conversion to ω-Ethoxycarbonyl Aldoximes under Alkaline Conditions
Moorhoff, Cornelis M.,Paquette, Leo A.
, p. 703 - 710 (2007/10/02)
A useful procedure for effecting the direct unsymmetrical cleavage of an enolizable ketone to an oximino ester has been developed.The process begins by deprotonation with LDA and is followed by the addition of ethyl nitrite in THF at low temperature.Rapid reaction customarily ensues with resultant overall nitrosolysis.Of particular importance is the facile application of this procedure to substrate ketones that are otherwise sensitive to acidic environments.This feature is exemplified in particular in the case of syn- and anti-sesquinorbornenones 34 and 35, access to which is described for the first time.Since the entire process is executed in a single flask, the methodology is very convenient to implement in practice.
Stereoselectivity of Organometallic Reagents Addition to 7-Oxabicyclohept-5-en-2-one
Arjona, Odon,Pradilla, Roberto Fernandez de la,Mallo, Araceli,Perez, Sonia,Plumet, Joaquin
, p. 4158 - 4164 (2007/10/02)
The reaction between 7-oxabicyclohept-5-en-2-one and a variety of organolithium, Grignard, and organocuprate reagents is described.Organolithium and Grignard reagents yield the expected endo alcohols with high selectivity.Alternatively, lithium organocuprates add with high stereoselectivity to the hindered endo face of the carbonyl functionality to afford the corresponding exo alcohols.
Alkylation and Oligomerization of the Lithium Enolate of 2-Norbornenones. Stereochemical Consequences of Enolate Aggregation
Horner, John H.,Vera, Marisol,Grutzner, John B.
, p. 4212 - 4220 (2007/10/02)
Alkylation of the lithium enolate of norbornenone in THF with alkyl halides gave a single trimeric oligomer containing one alkyl group as the major product.The structure of this diastereomer has been determined by 1H and 13 2-D NMR techniques and analysis of relaxation times.Direct reaction in the aggregated enolate with the Zimmerman-House-Jackman cubic structure is implied.Compounds with a 7-anti substituent could be alkylated in satisfactory yield.The use of the dimethylhydrazone anion as an enolate equivalent gave good yields of 3-alkylnorbornenones (methyl, n-hexyl, benzyl). 1H and 13C NMR data for products and intermediates are reported.
