Zirconocene-Mediated and/or Catalyzed Unprecedented Coupling Reactions of Alkoxymethyl-Substituted Styrene Derivatives
作者:Yutaka Ikeuchi、Takeo Taguchi、Yuji Hanzawa
DOI:10.1021/jo0502293
日期:2005.5.1
through an aromatic conjugate system giving metalated o-quinodimethane species, and (iii) transfer of zirconium metal to the benzylic position. Through use of a catalytic amount of “Cp2Zr”, however, unprecedented homo-coupling reactions (dimerization) of o-(alkoxymethyl)styrene derivatives occurred to give a tetracyclic compound. On the other hand, reactions of o-(1-alkoxyisopropyl)styrene derivatives
Copper-catalyzed acylations of o-vinylbenzylzirconocene intermediate and synthetic application toward steroid skeleton
作者:Yutaka Ikeuchi、Takeo Taguchi、Yuji Hanzawa
DOI:10.1016/j.tetlet.2004.04.049
日期:2004.5
Benzylzirconocene intermediate, which was readily prepared by a reaction of o-alkoxymethylstyrene with `Cp2Zr' under mild conditions, reacted with acyl chlorides in the presence of a catalytic amount of CuBr–SMe2 to give ketone derivatives in moderate to good yields.
Copper-catalyzed allylations of o-vinylbenzylzirconocene intermediate
作者:Yutaka Ikeuchi、Takeo Taguchi、Yuji Hanzawa
DOI:10.1016/j.tetlet.2004.03.097
日期:2004.5
Benzylzirconocene intermediate, which was readily prepared by the reaction of o-alkoxymethylstyrene with `Cp2Zr' under mild conditions, reacted with allylic halides or phosphates in the presence of catalytic amount of CuCl to give allylated products in good yields.
Copper-Catalyzed Allylations of Zirconocene Intermediates Generated from <i>o</i>-Alkenyl or <i>o</i>-Alkynylbenzyl Ether Derivatives and Zirconocene−Butene Complex
作者:Yutaka Ikeuchi、Takeo Taguchi、Yuji Hanzawa
DOI:10.1021/jo048860b
日期:2005.1.1
o-Alkenyl or alkynyl benzylzirconocene intermediate, which was readily generated by the reaction of 2-alkoxymethyl-styrene or 2-alkoxymethyl-1-(trimethylsilylethynyl)-benzene derivative with zirconocene-butene complex (Negishi reagent, "Cp2Zr"), reacted with allyl or propargyl halides in the presence of a catalytic amount of CuCl to give allylation or allenylation products. Conversion to Dane's diene, which is a key intermediate for estrone synthesis, was efficiently carried out by enyne olefin metathesis of the allylation products.
POGOSYAN G. M., XIMIYA NEPREDELNYX SOEDIN., (EREVAN), 1979, HO 1, 159-179