Alkenes reaction with alkyl halides

CLASSIFICATION OF REACTIONS BY TYPE OF COMPOUND SYNTHESIZED 16-47 Reaction of phosphines with Michael alkenes or with alkyl halides... 

The photolysis of CpPbR3 in the presence of various reagents was also investigated. Some differences were observed compared with the analogous tin compounds. The chemistry observed is summarized in Scheme 14, the main differences from CpSnR3 being the lack of reaction with alkyl halides or alkenes. 

Literature procedures for the synthesis of hydroperoxides include the preparation from hydrogen peroxide (via reaction with alkyl halides, -phosphites, -suEonates, alkenes. 

Alkylation is a very broad reaction type and it can, depending on the nature of the alkylating agent, proceed either as a substitution or as an addition reaction. The alkylation by substitution of, for example, aromatic hydrocarbons, phenols or amines is based on the reaction with alkyl halides or alcohols. Some evidence indicates that, at least partly, the alkylation proceeds through the intermediate formation of alkenes from the alkylating agent when the reaction is conducted at atmospheric pressure and at high temperature. 

Addition also occurs with ethylene and with activated alkenes, such as styrene, butadiene, tri-methylsilylethylene and phenylthioethylene, and provides in all cases the corresponding cyclopiopanes in good yield (Sdieme 93). > Interestingly, Ae a-selenoall llithiums do not react with Ae C—C bond at lower temperatures so diat the anion is sdll available for reaction with alkyl halides or carboiyl compounds (Scheme 92, compare a with b). 

Trimethylsilyl-l-alkenes. The lithium reagent is prepared from the corresponding selenide by treatment with BuLi. Its reaction with alkyl halides provides the allylsilanes. 

Reduction of Co2(CO)g with sodium-amalgam in THF solution gives Na[Co(CO)4]. Na[Co(CO)4] has high nucleophilicity, and the reaction with alkyl halides gives alkyl-cobalt complexes. It is generally difficult to isolate the alkylcobalt complexes, but in the presence of alkenes and alkynes, acylated compounds are obtained in good yields (eq (10)) [13]. 

Reactions of lithium alkyls are generally considered to be carbanionic in nature, but in reactions with alkyl halides free radicals have been detected by electron spin resonance.32 Lithium alkyls are widely employed as stereospecific catalysts for the polymerization of alkenes, notably isoprene, which gives up to 90% of 1,4-cA-polyisoprene numerous other reactions with alkenes have been studied.33 The TMED complexes again are especially active not only will they polymerize ethylene but they will even metallate benzene and aromatic compounds, as well as reacting with hydrogen at 1 atm to give LiH and alkane. 

The photolysis of a mixture of the alkene RCH=CH2 and (382) afforded (383) in good to high yields. The treatment of a large variety of a-thiomethyl- and a-selenomethyl phosphonates with BusSnH-AIBN results in their desulfurization or deselenation. The deselenation of phosphinoselenoic esters, e.g. (384), occurs imder attack by organometallic reagents, and ensuing reaction with alkyl halides provides phosphine oxides. ... 

Chapter 10 introduces the acid-base chemistry of molecules that contain the C=C and C C functional groups. Related reactions that do not fall under the acid-base category are also presented. Chapter 11 uses nucleophiles, which are loosely categorized as specialized Lewis bases, in reactions with alkyl halides. These are substitution reactions. Chapter 12 shows the acid-base reaction of alkyl halides that leads to alkenes (an elimination reaction), and Chapter 13 ties Chapters 11 and 12 together with a series of simplifying assumptions that allows one to make predictions concerning the major product. 

Some reactions of Pd(PPh3)4 are given in Fig. 5.18. The platinum derivative behaves similarly. Sulphur dioxide acts as a Lewis acid. The reactions with alkyl halides usually follow the Sj 2 mechanism, although free radical pathways can also participate. The reactions of aryl halides, which are normally rather unreactive towards nucleophiles are of interest. The palladium complexes catalyse the arylation of alkenes (the Heck reaction) by the following cycle ... 

Whereas dibutylboron enolates may be used as specific enolates in aldol condensations, their reactions with alkyl halides are relatively poor. However, the addition of one equivalent of lithium 2-dimethylaminoethoxide results in site-specific mono-a-alkylation in excellent yield. Organotin enamines add to electrophilic alkenes such as acrylonitrile. The use of an optically active... 

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