66051-36-3Relevant articles and documents
Stereoselective Halo-Succinimide Facilitated α-Halogenations of Substituted α-Trialkylsilyl-β-Substituted-α,β-Unsaturated Esters
Jennings, Michael P.,Probasco, Kristina C.
, p. 8945 - 8954 (2021/07/20)
The NXS (X = Cl, Br)-mediated halogenation of a series of (E)-α-trimethylsilyl-β-alkyl(aryl)-α,β-unsaturated esters in dimethylformamide (DMF) has furnished (Z)-β-substituted-α-halogenated-α,β-unsaturated ester products in moderate to high isolated yields (58-90%) with dr values of >20:1 coupled with the inversion of olefin stereochemistry. The reaction process was hypothesized to include an initial halonium cation intermediate, followed by regioselective ring opening with DMF. Subsequentanti-E2-type concomitant elimination allowed for the stereoselective formation of the product vinylic bromo-and chloroesters.
A convenient method for the synthesis of (Z)-α-haloacrylates: Lewis base-catalyzed carbonyl olefination using α-halo-C,O-bis(trimethylsilyl)ketene acetals
Michida, Makoto,Toriumi, Takako,Mukaiyama, Teruaki
experimental part, p. 3261 - 3262 (2009/08/09)
A highly useful method for the stereoselective synthesis of (Z)-α-haloacrylates from various aldehydes that uses α-halogenated ethyl-C,O-bis(trimethylsilyl)ketene acetals in the presence of a Lewis base catalyst such as acetate salts was established. This
Highly selective reaction of α-halo-αβ-unsaturated esters with ketones or aldehydes promoted by SmI2: An efficient alternative access to Baylis-Hillman adducts
Concellon, Jose M.,Huerta, Monica
, p. 4714 - 4719 (2007/10/03)
A samarium diiodide promoted addition of aromatic or aliphatic β-substituted-α-halo-α,β-unsaturated esters 1 or 3 to both ketones (in THF) and aldehydes (in acetonitrile) led to (Z)-2-(1-hydroxyalkyl)- 2,3-alkenoates 2 and 4 in good yields and very high stereoselectivity. This method constitutes an efficient and valuable alternative to the synthesis of Baylis-Hillman adducts. A mechanism is proposed to explain this transformation.
