A complementary approach to conjugated N-acyliminium formation through photoredox-catalyzed intermolecular radical addition to allenamides and allencarbamates

• Olusesan K. Koleoso,
• Matthew Turner,
• Felix Plasser and
• Marc C. Kimber

Beilstein J. Org. Chem. 2020, 16, 1983–1990, doi:10.3762/bjoc.16.165

• nucleophilic addition at the α-position giving the observed N,N’-allylaminal product 43. Conversely, addition of a nucleophile at the γ-position of E-42 gives the observed Z-enamide 44; and addition at the γ-position of Z-42’ gives the same observed Z-enamide 44 after C–N bond rotation. Conclusion In

Towards the total synthesis of chondrochloren A: synthesis of the (Z)-enamide fragment

• Jan Geldsetzer and
• Markus Kalesse

Beilstein J. Org. Chem. 2020, 16, 670–673, doi:10.3762/bjoc.16.64

• Hannover, Germany 10.3762/bjoc.16.64 Abstract The stereoselective synthesis of the (Z)-enamide fragment of chondrochloren (1) is described. A Buchwald-type coupling between amide 3 and (Z)-bromide 4 was used to generate the required fragment. The employed amide 3 comprising three chiral centers was

• ′-dimethylethane-1,2-diamine. Keywords: cross coupling; myxobacteria; natural product; ribolactone; Z-enamide; Introduction In the course of our program to provide synthetic access to biologically active natural products we targeted complex polyketides and depsipetides [1][2][3][4][5][6][7][8][9][10]. One

• particular group of compounds of particular focus in our research activities are natural products with enamide moieties [11]. Among these, chondrochloren having a (Z)-enamide moiety features a rare structural motif. The myxobacterial metabolite chondrochloren A (1) was isolated from Chondromyces crocatus