Regiospecific additions of some simple dienes to haloquinones
作者:Louise Boisvert、Paul Brassard
DOI:10.1016/s0040-4039(00)81953-x
日期:1983.1
Some simple dienes have been shown to react regiospecifically with haloquinones; the adducts can be oxidized without loss of the oxygenated function or aromatized to a variety of natural products and useful intermediates.
Reactions of ketene acetals—IX11Part VIII. J. Org. Chem. 41, 3018 (1976).
作者:Jean-Louis Grandmaison、Paul Brassard
DOI:10.1016/0040-4020(77)80312-8
日期:——
react with ketene acetals and give benzofurans, but in the presence of acetic acid, naphthoquinones are produced in variable yields. Some aspects of the reaction have been studied and the method has been applied to the synthesis of useful intermediates and of derivatives of some naturally occurring naphthoquinones such as tri-O-methylflaviolin 20 and tetra-O-methylspinochrome B 23. Benzoquinones also react
The Regiospecific Substitution of Halogenated Quinones by Sulfonamides
作者:Colette Mongrain、Linda Lee、Paul Brassard
DOI:10.1055/s-1993-25919
日期:——
Sulfonamides of anthranilic esters react regiospecifically with halogenated benzo- and naphthoquinones in the presence of fluoride ions in dimethylformamide. Highly substituted products are thus made available for conversion to a wide variety of highly substituted acridones some of which are difficult to obtain by other means.
ruthenium complex-bound norvaline Boc-L-[Ru]Nva-OMe 1, in which the ONO-pincer ruthenium complex Ru(pydc)(terpy) 2 is tethered to the α-side chain of norvaline, has been demonstrated for the oxidation of methoxybenzenes to p-benzoquinones with a wide scope of substrates and unique chemoselectivity.
Reactions of ketene acetals-14 The use of simple mixed vinylketene acetals in the annulation of quinones
作者:Jacques Savard、Paul Brassard
DOI:10.1016/s0040-4020(01)91496-6
日期:1984.1
α,β- β, γ-unsaturated esters can be converted by strong base and chlorotrimethylsilane to the corresponding mixed vinylketene acetals which are shown to be particularly useful and generally applicable reagents for the regiospecific annulation of halogenoquinones. The reaction proceeds readily with a variety of substrates including benzoquinones.