Asymmetric Total Syntheses of (−)-Renieramycin M and G and (−)-Jorumycin Using Aziridine as a Lynchpin

Abstract

By exploring the triple reactivity of two aziridines and double nucleophilicity of two aromatics, convergent and versatile syntheses of the above four natural products were developed.

Total Syntheses and Biological Evaluation of Both Enantiomers of Several Hydroxylated Dimeric Nuphar Alkaloids

“…[18] The preparation of 2a – 4a was carried out in a similar fashion and in comparable yields. Selective mono-reduction of the C6′ hemiaminal over the one at C6 in 1a could be accomplished to give 1b .…”

Palladium-catalyzed C–N bond formation via direct C–H bond functionalization. Recent developments in heterocyclic synthesis

“…Mechanistic studies on kinetic isotopic effect of deuteriated substrates seem to exclude an alternative aminopalladation/b-H elimination way. The presence of bases is instead invoked to justify for the regioselectivity towards 7-vs 5-membered products [77]. Oxygen is used as the final oxidant.…”

Three‐Membered Heterocycles. Structure and Reactivity

“…Acetylide anions are also competent nucleophiles when a copper(I) catalyst is used, as demonstrated by the high-yielding conversion of the 2-alkylaziridine 102 into the homopropargylamine 104, resulting from attack at the less hindered carbon [149]. Wu and Zhu have used the diastereoselective addition of an aryl Grignard onto a chiral aziridine as a key step in their total synthesis of (-)-renieramycin M and G and (-)-Jorumycin [150].…”

“…The vinyl azide in this case was synthesized from the corresponding alkene (i.e., 182) through sequential bromination, azide displace- ment and dehydrobromination, a protocol used by Gilchrist and coworkers to access azirinyl esters [251,252]. More recently, Somfai and coworkers [253] reported a much improved yield of azirine 184 (>95%) by carrying out the thermolysis in methylene chloride at 150 C for 20 min in a sealed tube. Even at atmospheric pressure the process can be quite high yielding and remarkably tolerant to other functionality.…”