Synthesis of 2,5-Diaryl-1,5-dienes from Allylic Bromides Using Visible-Light Photoredox Catalysis
摘要:
Visible-light photoreductive coupling of 2-arylallyl bromides in the presence of the photocatalyst Ru(bpy)(3)(PF6)(2), a Hantzsch ester, and i-Pr2NEt gives 2,5-diaryl-1,5-dienes in high yield. This method avoids the use of stoichiometric metal reductants and is compatible with the presence of halogen, alkyl, electron-donating, and electron-withdrawing substituents on the aromatic ring.
Diastereoselective One-Pot Synthesis of 7- and 8-Substituted 5-PhenylmorphansProbes for Narcotic Receptor Mediated Phenomena. 45.
作者:Hwan Jung Lim、Jeffrey R. Deschamps、Arthur E. Jacobson、Kenner C. Rice
DOI:10.1021/ol2021862
日期:2011.10.7
Novel 7- and 8-alkyl and aryl substituted 5-phenylmorphans were synthesized from substituted allyl halides and N-benzyl-4-aryl-1,2,3,6-tetrahydropyridine by a highly efficient and diastereoselective reaction series, “one-pot” alkylation and ene-imine cyclization followed by sodium borohydride reduction. Mild cyclization conditions gave the desired substituted 5-phenylmorphans in good yield as a single
employing N-(aryl/alkylthio)succinimides as a thiolating reagent. The reaction involves the generation of an episulfonium ion followed by intramolecular trapping with alkenes, which offers access to diverse thiolated dehydropiperidines in good yield. In addition, the synthesis of dihydropyran and cyclohexene derivatives, as well as the conversion of the arylthiol moiety to useful functional groups, were
A tandem reaction for the synthesis of phenanthrenes from arynes and α-(bromomethyl)styrenes is reported. The transformation proceeds via an ene reaction of α-(bromomethyl)styrenes with arynes, followed by a [4 + 2] cycloaddition reaction. The reaction generates 9-benzylphenanthrene derivatives in moderate to excellent yields.