Diels–Alder reactions of polyfluorocyclohexa-1,3-dienes. Part I. Addition of alkynes to perfluorocyclohexa-1,3-diene. A route to ortho-disubstituted tetrafluorobenzenes
作者:L. P. Anderson、W. J. Feast、W. K. R. Musgrave
DOI:10.1039/j39690000211
日期:——
Perfluorocyclohexa-1,3-diene reacts with alkynes (I) by 1,4-addition to give, exclusively and in good yield,2,3-disubstituted-1,4,5,6,7,7,8,8-octafluorobicyclo[2,2,2]octa-2,5-dienes (II)(X = Y = CF3, Me, Ch2Cl, CO2Et; X = H, Y = CF3, Me, Ch2Cl, Ph; X = CF3, Y = Me) which eliminate tetrafluoroethylene on pyrolysis to give ortho-disubstituted tetrafluorobenzenes, or their further pyrolysis products (III)(X
全氟环己基1,3-二烯与炔烃(I)通过1,4-加成反应以排他性且高收率地生成2,3-二取代的1,4,5,6,7,7,8,8-八氟双环[2,2,2] oct-2,5-二烯(II)(X = Y = CF 3,Me,Ch 2 Cl,CO 2 Et; X = H,Y = CF 3,Me,Ch 2 Cl ,Ph; X = CF 3,Y = Me),其在热解时消除四氟乙烯,得到邻二取代的四氟苯或其进一步的热解产物(Ⅲ)(X = Y = CF 3,Me,H; X = H,Y = CF 3,Me,CH 2 Cl,CO 2 H,–C CH,CH CH·C 6 HF 4,Ph; X = CF 3,Y = Me)。