| 摘要 |
<p>NEW MATERIAL:A compound expressed by formula I {R<1> is H or lower alkyl; R<2> is H or formula IV [R<4> is (substituted) alkyl or formula VII (R<3> is H or protecting group of OH; A is S; m is 1-4; p is 0 or 1)]; n is 1-3} EXAMPLE:2,3-Dihydro-5-hydroxy-4,6,7-trimethyl-1-benzofuran-2-yl) methanol. USE:An antioxidant and synthetic intermediate therefore having excellent antioxidizing action and used for oxygen-sensitive organic materials. PREPARATION:A compound expressed by formula II (R<3> is protecting group of OH) is reacted with Mg to prepare a Grignard reagent, which is then reacted with a compound expressed by formula III (Y is halogen) in the presence of CuBr to afford a compound expressed by formula IV> The resultant compound is then reacted with a peracid expressed by formula V (R<5> is lower alkyl or aryl) and the protecting groups are subsequently eliminated and cyclized under acidic condition at the same time to provide the aimed compound expressed by formula I (R<2> and R<3> are H; n is 1).</p> |
