32222-49-4Relevant academic research and scientific papers
ORBITAL CONTROL OF STEREOCHEMISTRY IN ACID-CATALYSED ADDITION REACTIONS OF ENDO-TRICYCLO2.4>OCT-6-ENE
Battiste, Merle A.,Coxon, James M.,Simpson, Gregory W.,Steel, Peter J.
, p. 3137 - 3144 (1984)
The reaction of endo-tricyclo2.4>oct-6-ene 1 with methanol in the presence of catalytic amounts of toluene-p-sulphonic acid has been shown to give 2-exo- and endo-methoxybicyclooct-3-ene (2c) and (2d) and 2-endo-methoxybicyclooct-6-ene (13).The formation of 2-exo-methoxybicyclooct-3-ene (2c), the major product of reaction, has been probed by deuterium labelling experiments and a series of 6-exo-7-exo-dideuterobicyclooct-3-enes synthesised for (2)H, (1)H and (13)C NMR spectral analysis in order unambiguously to determine the stereochemistry of proton attack on endo-tricyclo2.4>oct-6-ene ( 1).The formation of 2-exo-methoxybicyclooct-3-ene (2c) has been determined to involve corner protonation of the cyclopropyl moiety and skeletal rearrangement to an allylic cation with a small but measurable memory effect.
Diastereodivergent synthesis of the C9-cyclopentanone chiral building blocks
Nagata,Kawamura,Ogasawara
, p. 1825 - 1834 (2007/10/03)
Diastereodivergent synthesis the C9-cyclopentanone chiral building block, serving as the non-tryptamine moiety of the Corynanthe type indole alkaloids and the related natural products, and its diastereomer has been developed from racemic norcamphor by employing lipase-mediated resolution via an allylic acetate intermediate having a bicyclo[3.2.1]octane framework. A potential of the latter diastereomer has been demonstrated by its conversion into (-)-semburin, a monoterpene isolated from Swertia japonica previously and obtained from the C9-block.
A lipase-mediated route to (+)-juvabione and (+)-epijuvabione from racemic norcamphor
Nagata, Hiroshi,Taniguchi, Takahiko,Kawamura, Mitsuhiro,Ogasawara, Kunio
, p. 4207 - 4210 (2007/10/03)
(+)-Juvabione and (+)-epijuvabione, natural sesquiterpenes exhibiting insect juvenile hormone activity, have been synthesized from (±)-norcamphor via the both enantiomeric intermediates having bicyclo[3.2.1]octane framework by employing a lipase-mediated kinetic ester-hydrolysis reaction and cyclopropane ring-expansion reaction as the key steps.
Alkylation of Allylic Derivatives. 8. Regio- and Stereochemistry of Alkylation of Allylic Carboxylates with Lithium Methylcyanocuprate
Goering, Harlan L.,Kantner, Steven S.
, p. 422 - 426 (2007/10/02)
Alkylation of 5-methyl-2-cyclohexenyl acetate (1-OAc) with lithium methylcyanocuprate (LiCu(CN)Me) is regiospecific (>90 percent excess γ-alkylation) and sterospecific (>95 percent anti alkylation).In the bicyclooct-3-en-2-yl system (3), alkylation is stereoselective (both isomers give exo alkylation) and regiospecific (excess γ-alkylation).Alkylation of trans-α-methyl-γ-mesitylallyl acetate (8-OAc) with LiCu(CN)Me gives 57 percent α- and 43 percent γ-alkylation as compared to >97 percent α-alkylation with LiCuMe2.Mechanistic implications are discussed.
2-Norbornanediazonium Ions Revisited
Kirmse, Wolfgang,Siegfried, Rainer
, p. 950 - 956 (2007/10/02)
The reactions of 2-norbornanediazonium ions have been reinvestigated with the aid of optically active and deuterium-labeled precursors.Enantiomeric purities were determined by direct VPC methods, and deuterium distributions by 2H NMR spectroscopy.The product pattern is strongly affected by the polarity of the solvent. exo-Diazonium ions 13 in water yield racemic exo alcohol (s,kΔ) of the norbornadiazonium ions.Optically active exo products are typical of nonpolar solvents and originate most probably from assymetric ion pairs.Model studies with optically active bicyclooct-3-en-2-amine (36) provide conclusive evidence that ion-pair colapse may lead to optically active products even in the case of delocalized achiral carbocations.
