Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871 (P.R. China), Fax: (+86) 10-62751708.
Chemistry. 2013 Sep 16;19(38):12859-66. doi: 10.1002/chem.201301618. Epub 2013 Aug 9.
A variety of ester-substituted cyclopentadiene derivatives have been synthesized by one-pot reactions of 1,4-dilithio-1,3-butadienes, CO, and acid chlorides. Direct deprotonation of the ester-substituted cyclopentadienes with Ae[N(SiMe3 )2 ]2 (Ae=Ca, Sr, Ba) efficiently generated members of a new class of heavier alkaline earth (Ca, Sr, Ba) metallocenes in good to excellent yields. Single-crystal X-ray structural analysis demonstrated that these heavier alkaline earth metallocenes incorporated two intramolecularly coordinated ester pendants and multiply-substituted cyclopentadienyl ligands. The corresponding transition metal metallocenes, such as ferrocene derivatives and half-sandwich cyclopentadienyl tricarbonylrhenium complexes, could be generated highly efficiently by metathesis reactions. The multiply-substituted cyclopentadiene ligands bearing an ester pendant, and the corresponding heavier alkaline earth and transition-metal metallocenes, may have further applications in coordination chemistry, organometallic chemistry, and organic synthesis.
已通过 1,4-二锂-1,3-丁二烯、CO 和酰氯的一锅反应合成了各种酯取代的环戊二烯衍生物。通过 Ae[N(SiMe3 )2 ]2（Ae=Ca、Sr、Ba）直接对酯取代的环戊二烯进行去质子化，可高效率地以良好至优异的收率生成一类新的重碱土（Ca、Sr、Ba）茂金属。单晶 X 射线结构分析表明，这些重碱土茂金属包含两个分子内配位的酯侧基和多取代的环戊二烯基配体。相应的过渡金属茂金属，如二茂铁衍生物和半夹心环戊二烯三羰基钌配合物，可以通过复分解反应高效地生成。带有酯侧基的多取代环戊二烯配体，以及相应的重碱土和过渡金属茂金属，可能在配位化学、有机金属化学和有机合成中有进一步的应用。
