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Alkane diols, stereoselective

Stereoselective hydrogenation ofl -diketones. Hydrogenation of 1,3-alkane-diones catalyzed by Ru2Cl4[(R)-l][N(C2H5)3] results in anf/-l,3-diols with high dias-tereoisomeric and enantiomeric excesses (equation I). Under the same conditions l-phenyl-l,3-butanedione (2) is reduced mainly to the (3-hydroxy ketone 3 in 98%... [Pg.41]

The simplest ggwi-dizincio alkane bis(iodozincio)methane [CH2(Znl)2] reacts with aldehydes, and with ketones in presence of a suitable activator or catalyst, to produce the corresponding olefinated compounds in good yields (equation 80). It has been shown that the nucleophihcity of the zinc atom in CH2(ZnI)2 can be enhanced by coordination of a heteroatom from a ligand or a solvent. Substrates which contain a suitably placed donor atom also lead to activation. For example, 1,2-diketones see Diketones) suchasbenzil (PhCO-COPh) undergo efi cient [2- -l] cycloaddition reactions with CH2(ZnI)2 (equation 81). The reaction is stereoselective, leading only to m-diol derivatives. [Pg.5245]

NR s not reactive toward hydrocarbons S = stereoselective epoxidation E = epoxidation HA = hydroxylation of alkanes OA = oxidation of alcohols to carbonyl compounds PO oxidation of phosphines to phosphine oxides OC = oxidative cleavage of alkenes K= ketonization of alkenes DO = hydroxylation of alkenes to diols AO al1ylic oxidation of alkenes. [Pg.351]

Typical procedure. 4-Hydroxymethyl l,3-dioxolan-2-one 991 [712) A stirred mixture of potassium hydrogen carbonate (10.0 g, 0.1 mol), 18potassium salt by filtration, the organic layer was washed with water and 991 was distilled at 152-160 °C/0.6-0.8 mmHg yield 4.83 g (41%) IR v ax = 3500, 1800 cm T The stereoselective conversion of 1,2-diols into alkane-l,2-diyl carbonates at room temperature by adding them to acetonitrile solutions containing or... [Pg.258]

The stereoselective conversion of 1,2-diols into alkane-1,2-diyl carbonates has been carried out at room temperature, without employing catalysts or toxic and/or polluting reactants, by adding the 1,2-diol and then the alkylating agent to a solutions of C206, COs", or HCOs" anions and tetraalkylammonium cations in acetonitrile. Such solutions can be easily prepared by simple electrochemical or chemical routes [713]. [Pg.301]


See other pages where Alkane diols, stereoselective is mentioned: [Pg.318]    [Pg.318]    [Pg.18]    [Pg.120]    [Pg.351]    [Pg.81]    [Pg.492]    [Pg.478]    [Pg.788]   


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Alkanes diols

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