Regiospezifische Herstellung von primären Allylacetaten (2-Alkenyl-acetaten)
作者:Antonio García Martínez、Angeles Cruces Villalobos、Manuel Oliver Ruiz
DOI:10.1055/s-1988-27464
日期:——
Regiospecific Preparation of Primary Allyl Acetates (2-Alkenyl Acetates) The reaction of primary, secondary and tertiary allyl alcohols 1 with anhydrous magnesium iodide in benzene gives regiospecifically the primary allyl iodides 2. The corresponding primary allyl acetates 3 are obtained regiospecifically by reaction of 2 with anhydrous sodium acetate in dimethylformamide.
A catalytic system consisting of sodium tungstate and methyltrioctylammonium hydrogensulfate effects oxidation of simple secondary alcohols to ketones using 3—30% H2O2 without any organic solvents. The oxidation can be conducted under entirely halide-free, mildly acidic conditions. A combination of tungstic acid and an appropriate quaternary ammoniumsalt also effects the alcohol dehydrogenation. The
Dehydrogenation of alcohols with allyl carbonates catalyzed by palladium or ruthenium complexes
作者:Ichiro Minami、Jiro Tsuji
DOI:10.1016/s0040-4020(01)81672-0
日期:——
alkyl allyl carbonates with a phosphine-free palladium catalyst in acetonltrile affords ketones or aldehydes in high yields. This new method of oxidation of alcohols via allyl carbonates can be applied to various alcohols except simple primary alcohols. The reaction proceeds under neutral conditions and hence various acid- or base-sensitive functional groups are not affected during the reaction. Ruthenium
Photoredox Activation of SF<sub>6</sub>for Fluorination
作者:T. Andrew McTeague、Timothy F. Jamison
DOI:10.1002/anie.201608792
日期:2016.11.21
We report the first practical use of SF6 as a fluorinating reagent in organic synthesis. Photoredoxcatalysis enables the in situ conversion of SF6, an inert gas, into an active fluorinating species by using visiblelight. Under these conditions, deoxyfluorination of allylic alcohols is effected with high chemoselectivity and is tolerant of a wide range of functional groups. Application of the methodology
Guiding a divergent reaction by photochemical control: bichromatic selective access to levulinates and butenolides
作者:Revannath L. Sutar、Saumik Sen、Or Eivgi、Gal Segalovich、Igor Schapiro、Ofer Reany、N. Gabriel Lemcoff
DOI:10.1039/c7sc05094a
日期:——
irradiation initiates E–Z isomerization of the carbon–carbon double bond, followed by one of two competing processes; namely, cyclization by transesterification or a 1,5-H shift and tautomerization. Quantum chemical calculations demonstrate that intermediates are strongly blue-shifted for the cyclization while red-shifted for the 1,5-H shift reaction. Hence, delaying the double bond migration by employing