Synthese aromatisch anellierter ϵ‐Lactone

Abstract

The synthesis of three isomeric benzoxepinones 2, 7 and 8 by oxidation of the w-diols 1 and 6 with silver carbonate on Celite is reported.Aus 6und y-Lactonen konnen rnit Arylalkylaminen Hydroxyamide hergestellt werden, die sich in Folgereaktionen zu tetracyclischen Ringsystemen cyclisieren lassen"]. Als Lactonkomponenten sollten nun die &-Lactone 3-Benzoxepin-2-on (2), 2-Benzoxepin-1-on (7) und 2-Benzoxepin-3-011 (8) eingesetzt werden. 1983 wurde die Synthese von 2['] beschrieben; fur 7 sind insgesamt drei sehr aufwendige Herstellungen bekannt 13-61.

Ring Expansions of Tetrahydroprotoberberines and Related Dibenzo[c,g]azecines Modulate the Dopamine Receptor Subtype Affinity and Selectivity

“…The synthesis of compounds 1-6 is outlined in Scheme 1. Ring expanded THPB homologues 3 and 5 were synthesized according to previously described procedures [3,4] hydroxy ester 9. Ring opening was performed after quaternization with methyl iodide under Birch conditions (liq.…”

“…After evaporation of the solvent, the residue was dissolved in water and extracted with ethyl acetate. The organic layer was dried over MgSO 4 and evaporated in vacuo. The resulting yellow oil was crystallized from methanol to yield the respective tetracycle.…”

“…The resulting yellow oil was crystallized from methanol to yield the respective tetracycle. Analytical data is given in reference [4]. The synthesis was performed according to a procedures described before [3], starting with a phenethylamine (2.4 mmol) and methyl[2-(2-hydroxyethyl)phenyl]acetate (2 mmol).…”

“…After suspending 1 mmol of the quaternary ammonium salts (11,12) in the liquid ammonia, small pieces of sodium were added to the stirred mixture until the developing blue colour remained for 10-15 min. The mixture was quenched with 1-2 drops of saturated aqueous NH 4 Cl. The ammonia was evaporated under nitrogen and the residue portioned between ether and water.…”

“…In the present study, we applied this ring-opening approach on ring-enlarged THPBs to obtain B-(3) and Chomologues 5, which were synthesized by Meise et al [3,4]. Compounds 3 and 5 were quaternized with methyl iodide, followed by cleavage of the central C-N bond with Na in liq.…”