Werner Tochtermann

A new approach to the [6]paracyclophane system: synthesis of 2,3-dicarbethoxy[6]paracyclophane

Abstract The reaction of the dibromide 1 with McMurrys reagent gives 2,3-dicarbethoxy[6]paracyclophane ( 2 ) in about 40% yield.

Die kristall- und molekülstrukture von [6]Paracyclophan-8,9-dicarbonsäuredimethylester

Zusammenfassung The structure of the title compound 1b was determined by X-ray crystallography: The para carbon atoms C-7 and C-10 are lifted out of the plane of the other four benzene carbons by 19.4 and 19.5°.

Optisch aktive γ-lactone aus cyclooctin und furan - synthese von (−)-muricatacin

Zusammenfassung The synthesis of (−)-(4R,5R)-muricatacin ((−)-3) from cyclooctyne and furan as starting materials is reported.

Zur konformation und intramolekularen beweglichkeit von [6]paracyclophan-8,9-dicarbonsäurediethylester)

The title compound 1 prepers the conformations 1a/1b predicted for [6]paracyclophane; the barrier for the intramolecular process la ⇌ 1b was found to be Δ G+ = 13.9 kcal/mol at +4°C.

Reaktionen des [6]paracyclophan-8,9-dicarbonsäurediethylesters: brom-addition und prisman-bildung

Abstract The title compound 1 adds bromine at 0°C and gives the dibromide 2 in 33 % yield; irradiation of 1 yields the prismane 3 in 56 % yield.

SYNTHESE STEREOISOMERER 4,7-EPOXY-HYDROAZULEN-5,6-DICARBONSAUREDIMETHYLESTER MIT LACTARAN-GERUST

Abstract Methylenation of the keto group of the cis -diester 1 by Wittig reaction gives under inversion on C-6 the trans -diester 2 . The revised stereochemistry of 2 was established by crystal structure analysis of the hydrogenation product 3 and by comparison of NMR data. On the other hand methylenation of 1 with the Nysted reagent leads to the cis -diester 5 which is hydrogenated to the trimethylhydroazulene 6 .

Reaktionen des [6]paracyclophan-8,9-dicarbonsäurediethylesters: cis-1,2-addition von brom und osmiumtetroxid an ein benzolderivat

Abstract The synthesis and structure determination of the cis-1,2-addition products of bromine and osmium tetroxide to the boat-shaped benzene derivative 1 are described.

Chirale Induktion bei der photochemischen Umlagerung von 3,6-Hexanooxepin-4,5-dicarbonsäureestern

Abstract Irradiation of an aqueous suspension of the crystalline diester 1d affords the (+)-(3aS, 6R, 8aR)-methanohydroazulene 2d in 45% yield with 83% de. The absolute configurations were established via the X-ray structural analysis of the dimenthylester (+)-2b and chemical transformations.

Eine eintopfsynthese von[6](2,5)furanophanen durch ringverengung von [6](3,6)oxepinophanen MIT rutheniumtetroxid ☆

A one-pot synthesis of [6](2,5)furanophanes by ring contraction of [6](3,6)oxepinophanes by means of ruthenium tetraoxide is described.

Die photoisomerisierung von 3,6-hexanooxepin-4,5-dicarbonsäureestern zu tricyclo[6.2.1.0 1,5] undec-9-en-(3a,6-methanooctahydroazulen)-derivaten

Abstract Irradiation of the 3,6-hexanooxepins 1a – 1c affords the tricyclo[6.2.1.0 1,5 ] undec-9-ene(3a,6-methanooctahydroazulene)derivatives 2a – 2c in about 50% yield.