Cross-metathesis reaction of α- and β-vinyl C-glycosides with alkenes
نویسندگان
چکیده
Cross-metathesis of α- and β-vinyl C-deoxyribosides and α-vinyl C-galactoside with various terminal alkenes under different conditions was studied. The cross-metathesis of the former proceeded with good yields of the corresponding products in ClCH2CH2Cl the latter required the presence of CuI in CH2Cl2 to achieve good yields of the products. A simple method for the preparation of α- and β-vinyl C-deoxyribosides was also developed. In addition, feasibility of deprotection and further transformations were briefly explored.
منابع مشابه
Synthesis of functionalized vinyl boronates via ruthenium-catalyzed olefin cross-metathesis and subsequent conversion to vinyl halides.
Functionalized vinyl pinacol boronates suitable for Suzuki cross-coupling reactions are synthesized using ruthenium-catalyzed olefin cross-metathesis of 1-propenyl pinacol boronate and various alkenes, including functionalized and 1,1-disubstituted alkenes. The resultant boronate cross products are stereoselectively transformed into predominantly Z-vinyl bromides and E-vinyl iodides. The vinyl ...
متن کاملRuthenium-catalysed Z-selective cross metathesis of allylic-substituted olefins† †Electronic supplementary information (ESI) available: Experimental procedures and spectroscopic data for all new compounds. See DOI: 10.1039/c3sc52806e Click here for additional data file.
The Z-selective cross metathesis of allylic-substituted olefins is explored with recently developed ruthenium-based metathesis catalysts. The reaction proceeds with excellent stereoselectivity for the Z-isomer (typically >95%) and yields of up to 88% for a variety of allylic substituents. This includes the first synthesis of Z-α,β-unsaturated acetals by cross metathesis and their elaboration to...
متن کاملCross-metathesis reactions of vinyl-chlorins and -porphyrins catalyzed by a "second generation" Grubbs' catalyst.
The first application of olefin cross-metathesis with vinylchlorins and vinylporphyrins using a "second generation" Grubbs' catalyst is reported. Cross-metathesis products were obtained in good yields with high E-stereoselectivity.
متن کاملRelay cross metathesis reactions of vinylphosphonates
Dimethyl (β-substituted) vinylphosphonates do not readily undergo cross metathesis reactions with Grubbs catalyst and terminal alkenes. However, the corresponding mono- or diallyl vinylphosphonate esters undergo facile cross metathesis reactions. The improved reactivity is attributed to a relay step in the cross metathesis reaction mechanism.
متن کاملCross-metathesis of the vinyl group on tetrapyrrolic macrocycles: reactivity, selectivity, and mechanism.
To find a general strategy for modifying the peripheral structure of vinylchlorin and porphyrin substrates, cross-metathesis on the vinyl group of these tetrapyrrolic macrocycles was investigated. The N-heterocyclic carbene-containing ruthenium complex 3 efficiently catalyzed the cross-metathesis (CM) of vinylchlorins and vinylporphyrins with a variety of olefins in high E-stereoselectivity. Di...
متن کامل