The readily accessible 2-halogeno-1-trimethylsilyloxy-1,3-butadienes, e.g. CH2:CRCR1:CHOSiMe3 (R = H, Me; R1 = F, Cl) react smoothly with MeO2CC.tplbond.CCO2Me to afford 4-halophthalic esters, e.g. I. I (R = H, R1 = Fl) was subsequently converted into the ...
1992