by the regio- and stereoselective ring opening of β, γ, and δ-lactones with unsaturated substituents at the ω-position using organocopperreagents such as halomagnesium diorganocuprates or Grignard reagents in the presence of copper(I) iodide. Both the organocopperreagents with primary, secondary, tertiary alkyl, and phenyl groups gave the corresponding carbon homologated alkenoic acids in good yields
A convenient method for the synthesis of (E)-3-alkenoic acids by a regio- and stereoselective reaction of β-vinyl-β-propiolactone with organocopper reagents
β-Vinyl-β-propiolactone reacts regio- and stereoselectively with Grignard reagents in the presence of copper(I) catalyst or with diorganocuprates to afford (E)-3-alkenoic acids in high yields.
Transposition eventuelle lors de l'action de bromures β-ethyleniques CH2CHCH(R)CH2Br (R = CHCH2, C2H5, C6H5) sur le magnesium
作者:F. Gerard、Ph. Miginiac
DOI:10.1016/s0022-328x(00)87055-2
日期:1976.5
Reaction betweenβ-ethylenic bromides CH2CHCH(R)CH22Br and magnesium in ether has been studied. With R = CHCH2, it gives rise both to normal and rearranged Grignard reagents. With R = C2H5 and C6H5, only the normal Grignard reagent is formed.
反应betweenβ烯溴化物CH 2 CHCH(R)CH 2 2BR和在乙醚中的镁进行了研究。当R = CH = CH 2时,它会同时产生正常和重排的格氏试剂。当R = C 2 H 5和C 6 H 5时,仅形成普通的格氏试剂。
SATO TOSHIO; TAKEUCHI MASASHI; ITOH TOSHIYUKI; KAWASHIMA MASATOSHI; FUJIS+, TETRAHEDRON LETT., 1981, 22, NO 19, 1817-1820