107368-92-3Relevant articles and documents
Total syntheses of (±)-cis-trikentrin A and (±)-cis- trikentrin B via electrocyclic ring closures of 2,3-divinylpyrrolines
Huntley, Raymond J.,Funk, Raymond L.
, p. 3403 - 3406 (2006)
A convergent and versatile strategy for the diastereoselective syntheses of (±)-cis-trikentrin A and B in 10 and 12 steps, respectively, from commercially available N-BOC-2-pyrrolidinone is described. The key step in each of the total syntheses is the construction of the central benzene ring via a facile 6π-electrocyclic ring closure of an appropriately substituted 2,3-divinylpyrroline, in turn, readily available by a Stille coupling reaction.
Asymmetric hydrovinylation of vinylindoles. A facile route to cyclopenta[g]indole natural products (+)-cis-trikentrin A and (+)-cis-trikentrin B
Liu, Wang,Lim, Hwan Jung,Rajanbabu
, p. 5496 - 5499 (2012/05/20)
Vinylindoles undergo Ni(II)-catalyzed asymmetric hydrovinylation under very mild conditions (-78 °C, 1 atm ethylene, 4 mol % catalyst) to give the corresponding 2-but-3-enyl derivatives in excellent yields and enantioselectivities. Hydroboration of the alkene and oxidation to an acid, followed by Friedel-Crafts annulation, gives an indole-annulated cyclopentanone that is a suitable precursor for the syntheses of cis-trikentrins and all known herbindoles. For example, the cyclopentanone from 4-ethyl-7-vinylindole is converted into (+)-cis-trikentin A in four steps (Wittig reaction, alkene isomerization, diastereoselective hydrogenation, and nitrogen deprotection). The previous synthesis of this molecule from (S)-(-)-malic acid involved more than 20 steps and a preparative HPLC separation of diastereomeric intermediates.
Total Synthesis of (+/-)-cis-Trikentrin A
Wiedenau, Paul,Monse, Barbara,Blechert, Siegfried
, p. 1167 - 1176 (2007/10/02)
Two patways towards the construction of the trikentrin skeleton are presented, one leading to the total synthesis of (+/-)-cis-Trikentrin A (1).The key step is the intramolecular Heck coupling of the triflate 21 to form the five-membered ring of the indenes 22 and 23.
