91153-93-4Relevant articles and documents
Copper-Mediated SN2′ Allyl-Alkyl and Allyl-Boryl Couplings of Vinyl Cyclic Carbonates
Miralles, Núria,Gómez, José Enrique,Kleij, Arjan W.,Fernández, Elena
, p. 6096 - 6099 (2017/11/27)
A method for the copper-catalyzed borylmethylation and borylation of vinyl cyclic carbonates through an SN2′ mechanism is reported. These singular reactions involve selective SN2′ allylic substitutions with concomitant ring opening of the cyclic carbonate and with extrusion of CO2 and formation of a useful hydroxyl functionality in a single step. The stereoselectivity of the homoallylic borylation and allylic borylation processes can be controlled, and synthetically useful unsaturated (E)-pent-2-ene-1,5-diols and (E)-but-2-ene-1,4-diols are accessed.
Grignard Addition Reactions to 1,4-Difunctionalized But-2-ynes
Silva, Anthony N. De,Francis, Craig L.,Ward, A. David
, p. 1657 - 1672 (2007/10/02)
Trisubstituted alkenes of E geometry have been prepared by anti addition of Grignard reagents to 1,4-difunctionalized but-2-ynes.Addition of primary, secondary and aromatic Grignard reagents to but-2-yne-1,4-diol provided (E)-2-substituted but-2-ene-1,4-diols as major products along with the corresponding 2-substituted buta-2,3-dien-1-ols.Addition of phenylmagnesium bromide to the mono- and di-methyl ethers of but-2-yne-1,4-diol gave 2,3-diphenyl-1,3-diene.Treatment of 4-dimethylaminobut-2-yn-1-ol with primary alkyl and alkenyl Grignard reagents afforded the 2-substituted anti addition product regiospecifically, stereospecifically and in high yield.Reaction of 1-dimethylamino-4-methoxybut-2-yne with butylmagnesium bromide provided only the 3-substituted anti addition product in good yield.