posted on 2015-01-12, 00:00authored byRan Lin, Ka-Ho Lee, Herman H. Y. Sung, Ian D. Williams, Zhenyang Lin, Guochen Jia
Treatment of Na[Re(CO)5] with methyl 3-(naphthalen-1-yl)propiolate
(NpCCCO2Me) followed by acetyl chloride and alcohols
ROH (R = Me, nPr) afforded the rhenacyclobutadiene
complexes Re{-C(Np)C(CO2Me)C(OR)}(CO)4. Reactions of these rhenacyclobutadiene complexes with HCCOEt
produced the rhenabenzene complexes Re{-C(Np)C(CO2Me)C(OR)CHC(OEt)}(CO)4 and new rhenacyclobutadienes with a pendant vinyl substituent Re{-C(Np)C(C(OR)CH(CO2Et))C(OMe)}(CO)4. In the vinyl-substituted
rhenacyclobutadiene products, the ethyl of the ester group is from
the alkyne HCCOEt, the alkyl of the ReC(OR) group is from
the ester group of the starting rhenacyclobutadienes, and the alkyl
group of the OR of the vinyl substituent is from the ReC(OR) group
of the starting rhenacyclobutadienes. A plausible mechanism for the
formation of the vinyl-substituted rhenacyclobutadienes is discussed.