Vinyl selected examples

Some selected examples of palladium-catalyzed reduction of vinyl and aryl triflates are summarized in the Table. 

Geminal selectivity is also observed in cases where the bulky substituent is in a vinylic position . Examples with compounds 60-65 are shown in Table 10. 

Table 6.13 Selected examples of the epoxidation of vinyl sulfones.

Table 29 Selected examples of vinyl fluorides synthesis according to Scheme 108...

Berthelette and coworkers [144] developed the synthesis of vinyl ethers 328 (Scheme 111) from (z-alkoxymethyl BT sulfones 326 and various aldehydes or ketones 327. The olefination reaction was carried out using LHMDS in THF at 0 °C. In general, very good chemical yields and poor stereoselectivities were recorded. Selected examples are presented in Table 31. 

Finally some selected examples will further demonstrate the synthetic versatility of the Claisen rearrangement when different functionalities in either the allyl or the vinyl part of the system are present (Scheme 70). " By appropriate choice of substituents in strategically important positions, systems can be built up which are suitable for further elaboration in a synthetic scheme. 

Selected examples of 1,1-dibromocyclopropanes, prepared from vinylic-, allylic- and homo-allylic halides are collected in Table 29. Low yields of some cyclopropanes are possibly due to their troublesome separation from the other products. ... 

The reaction was successfully applied to both electron-rich and electron-poor 4-nitrophenyl carboxylates among them, the conversion of the electron-deficient esters was found to be faster and more efficient. Many functional groups are tolerated on both the side of the carboxylic ester (halo, keto, formyl, ester, cyano, nitro and protected amino groups, heterocyclic and a,-unsaturated carboxylic esters) and of the alkene (electron-rich alkyl-substituted alkenes, electron-poor acrylate derivatives, trimethylvinylsilane as an ethylene surrogate). The cinnamate derivatives could become particularly useful substrates, since the availability of the synthetically equivalent vinyl halides is rather limited. In analogy to conventional Mizoroki-Heck chemistry, linear (Zi)-substituted alkenes are predominantly but not exclusively obtained. Selected examples are shown in Table 4.1. 

The published literature, particularly the patent literature, of vinyl ester polymerization is very extensive. No attempt will be made here to cover this field comprehensively. Rather, selected examples will be drawn from various sources which represent state-of-the-art methods for the preparation of these polymers from both a commercial and a laboratory point of view. 

Abstract Transition metal-catalyzed cycloadditions of cyclopropanes have been well developed over the past several decades, leading to numerous new types of cycloadditions which are complementary to the traditional cycloadditions for the synthesis of carbocycles. Cycloadditions of vinylcyclopropanes (VCPs) and methylenecyclopropanes (MCPs) constitute two main aspects of this field. VCPs can act either as five-carbon synthons or three-carbon synthons, depending on whether the vinyl substituent is acting as an additional two-carbon synthon or not. As five-carbon synthons, VCPs are involved in [5-1-1], [5-1-2], [5-I-2-1-1], and [5+1+2-I-1] cycloadditions. As three-carbon synthons, VCPs are mainly involved in [3-1-2] and [3-1-2-t-l] cycloadditions. MCPs mostly act as three-carbon synthons and can have [3-1-2] cycloadditions with different jt systems. Other types of cycloadditions involving MCPs are also reviewed, such as [3-rl], [3+2+2], and [4+3+2] cycloadditions. CycloadditirMis of some other unusual cyclopropane derivatives are also introduced briefly. The cycloadditions of VCPs and MCPs have found applications in total synthesis and some representative molecules are tabulated as selected examples. 

Selected examples for the copper-catalyzed cross-coupling of lactam and heteroaryl vinyl halides Sun et al. [155], Meketa and Weinreb [156, 157], Yang et al. [158]. 

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