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Lombardo’s reagent

Treatment of 44 with Lombardo s reagent (TiCl4/Zn/CH2Br2) (27) in CH2CI2 gave a mixture of the desired methylenation product 45 (24% yield)... [Pg.11]

Two additional titanium reagents that have been used for olefination reactions are Cp2TiMc2, developed by Petasis, 25 d Lombardo s use b Oshima s reagent (Zn—CH2Br2—TiCU). Cp2TiMc2 reagent is... [Pg.680]

Actually, this method was claimed not to be reproducible and was modified by Lombardo in 1982 [12]. Lombardo applied Takai and Oshima s procedure to the methylenation of gibberellin derivative with Zn (pure, without lead)-CH2Br2-TiCl4, and only decomposition of the substrate was observed. He showed an improved procedure. According to Lombardo s report, the aging period for the preparation of the reagent should be three days (Scheme 8.4). This method is effective for methylenation of ketones. Methylenation of the ester group with this system did not proceed efficiently, except for a few examples [13]. [Pg.350]

See other pages where Lombardo’s reagent is mentioned: [Pg.661]    [Pg.462]    [Pg.1767]    [Pg.462]    [Pg.391]    [Pg.661]    [Pg.462]    [Pg.1767]    [Pg.462]    [Pg.391]    [Pg.651]    [Pg.749]    [Pg.749]    [Pg.681]    [Pg.12]    [Pg.749]    [Pg.653]    [Pg.177]    [Pg.156]    [Pg.1781]   
See also in sourсe #XX -- [ Pg.462 ]



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Alkenes from ketones by Lombardo’s reagent

Lombardo reagent

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