727652-80-4Relevant academic research and scientific papers
Stereoselective olefination reactions promoted by Rieke manganese
Concellon, Jose M.,Rodriguez-Solla, Humberto,Del Amo, Vicente,Diaz, Pamela
experimental part, p. 2634 - 2645 (2009/12/06)
A study of the advantages of using manganese, an inexpensive and nontoxic metal, to perform stereoselective β-elimination reactions and to promote sequential olefination reactions of aldehydes to obtain α,β- unsaturated esters and amides is presented. Various elimination reactions, all of them characterized by occurring with complete stereoselectivity and in high yields, were performed using active manganese (Mn*) as metalating agent. This ability of manganese has been applied to develop a novel and direct synthesis of (E)-α,β-unsaturated esters or amides and (Z)-α,β-unsaturated α-halo esters and α-choroamides through a Mn*-mediated sequential olefination protocol of aldehydes with dichloro esters or amides and trihalo esters or trichloroamides, respectively. Georg Thieme Verlag Stuttgart.
Stereoselective synthesis of (Z)-α-haloacrylic acid derivatives, and (Z)-haloallylic alcohols from aldehydes and trihaloesters or amides promoted by Rieke manganese
Concellon, Jose M.,Rodriguez-Solla, Humberto,Diaz, Pamela
experimental part, p. 2934 - 2940 (2009/02/02)
A Mn*-promoted sequential process directed toward the synthesis of (Z)-α-halo-α,β-unsaturated esters or amides is described. In both cases, the process takes place with complete Z-stereoselectivity. In addition, (Z)-α-chloro-α,β-unsaturated ketones and carboxylic acids, and (Z)-haloallylic alcohols were readily prepared from (Z)-α-halo-α,β-unsaturated amides derived from morpholine, or esters. A mechanism has been proposed to explain the sequential process and the stereoselectivity observed. The Royal Society of Chemistry.
Synthesis of (Z)-α-chloro-α,β-unsaturated esters with complete stereoselectivity promoted by samarium diiodide
Concellón, José M.,Huerta, Mónica,Llavona, Ricardo
, p. 4665 - 4667 (2007/10/03)
Stereoselective β-elimination in α,α-dichloro-β- hydroxyesters 2 was achieved by using samarium diiodide, yielding (Z)-α-chloro-α,β-unsaturated esters 1. The starting compounds 2 were easily prepared by reaction of the lithium enolate of ethyl dichloroacetate with different aldehydes at -78°C. A mechanism to explain this process is proposed.
