Protecting‐Group‐Free Total Synthesis of (E)‐ and (Z)‐Alstoscholarine

Palladium‐Catalyzed Decarboxylative Vinylation of Potassium Nitrophenyl Acetate: Application to the Total Synthesis of (±)‐Goniomitine

“…In connection with our continuous interest in the total synthesis of indole alkaloids by late-stage construction of the indole nucleus, [9,10] we thought to build the whole tetracyclic scaffold of goniomitine from functionalized cyclopentene 2 by a one-pot integrated oxidation/reduction/cyclization (IORC) sequence (Scheme 1). [11] Although different multi-step syntheses of 2 could be envisaged, [9d] the as-yet unknown direct decarboxylative coupling of two readily accessible building blocks (the substituted potassium salt of o-nitrophenyl acetate 3 and vinyl triflate 4) was deemed to be the method of choice.…”

Palladium‐Catalyzed Decarboxylative Vinylation of Potassium Nitrophenyl Acetate: Application to the Total Synthesis of (±)‐Goniomitine

“…In connection with our continuous interest in the total synthesis of indole alkaloids by late‐stage construction of the indole nucleus,9, 10 we thought to build the whole tetracyclic scaffold of goniomitine from functionalized cyclopentene 2 by a one‐pot integrated oxidation/reduction/cyclization (IORC) sequence (Scheme ) 11. Although different multi‐step syntheses of 2 could be envisaged,9d the as‐yet unknown direct decarboxylative coupling of two readily accessible building blocks (the substituted potassium salt of o ‐nitrophenyl acetate 3 and vinyl triflate 4 ) was deemed to be the method of choice.…”

Enantioselective Total Synthesis of (+)‐Nordasycarpidone, (+)‐Dasycarpidone, and (+)‐Uleine

“…Our group has recently accomplished an enantioselective total synthesis of condyfoline ( 11 ) [20] through a key TiCl 3 ‐mediated reductive cyclization of tetrasubstituted alkene bearing a 2‐nitrophenyl substituent [21] as well as alstilobanine C ( 8 ) and undulifoline ( 9 ) featuring a late stage construction of both the indole and the piperidine rings by way of a double reductive cyclization cascade ( Scheme 1 ,b ) [22] . As a continuation of our interest in the synthesis of indole alkaloids containing a bridged bicyclic ring system, [23–26] we envisaged to develop an alternative strategy to reach the tetracyclic compound 1 . A retrosynthetic analysis of natural products 2 – 4 involving 1 as an advanced intermediate is depicted in Scheme 2.…”