403656-70-2

Upstream product

• 403656-65-5 (4R)-4-(diphenylmethyl)-3-[(3R)-3-(ethoxycarbonyl)-4-(3'-methoxyphenyl)]butanoyl-2-oxazolidinone 
• 90110-63-7 3-methoxybenzyl iodide 
• 403656-69-9 (R)-4-(diphenylmethyl)-3-[(2R,3R)-2-(3'-methoxyphenyl)methyl-3-(ethoxycarbonyl)-4-(3'-methoxyphenyl)]butanoyl-2-oxazolidinone 

Downstream Products

• 80704-91-2 (3R,4R)-3,4-bis<(3-methoxyphenyl)methyl>dihydro-2(3H)-furanone 

Relevant academic research and scientific papers

Free-radical-mediated conjugate additions. Enantioselective synthesis of butyrolactone natural products: (-)-Enterolactone, (-)-arctigenin, (-)-isoarctigenin, (-)-nephrosteranic acid, and (-)-roccellaric acid

Lewis acid-mediated conjugate addition of alkyl radicals to a differentially protected fumarate 10 produced the monoalkylated succinates with high chemical efficiency and excellent stereoselectivity. A subsequent alkylation or an aldol reaction furnished the disubstituted succinates with syn configuration. The chiral auxiliary, 4-diphenylmethyl-2-oxazolidinone, controlled the stereoselectivity in both steps. Manipulation of the disubstituted succinates obtained by alkylation furnished the natural products (-)-enterolactone, (-)-arctigenin, and (-)-isoarctigenin. The overall yields for the target natural products were 20-26% over six steps. Selective functionalization of the disubstituted succinates obtained by aldol condensation gave the paraconic acid natural products (-)-nephrosteranic acid (8) and (-)-roccellaric acid (9). The overall yield of the natural products 8 and 9 over four steps was 53% and 42%, respectively.