Reactions with Alkylating Agents

A. S. Alves, D. S. Moore, R. A. Andersen, and G. Wilkinson, Triphenylphosphonium and Trimethylphosphonium Hexachloroosmates(IV) and Their Reactions with Alkylating Agents Methyl and Trimethylsilylmethyl Osmium Compounds tranj-Dichlorote-trakis(trimethylphosphine)osmium(II) Tetrakis(trimethylsilylmethyl)oxoosmium(VI), Polyhedron 1, 83-87 (1982). 

Whitesell and Whitesell" have tabulated some of the many types of electrophilic reagents that C-al-kylate metallated imines. These are potent nucleophiles and undergo substitution reactions even with weakly electrophilic species such as epoxides and oxetanes. Lithiated ketimines and aldimines have been frequently used in reactions with alkylating agents containing latent 2-keto (or aldehydo) groupsor 3-keto (or aldehydo) groups. ... 

Phenoxaphosphines with P(III), e.g. the 10-phenyl compound (323), are much slower in their reaction with alkylating agents than triphenylphosphine <79PS(7)309). On the other hand, arylation can be achieved (PhBr/AICI3,210 °C, 2 h), giving the 10,10-diphenyl phosphonium salt (327) (isolated as the iodide) <403CS1192, 533CS3746). 

RP Phases. The surface properties of silanol may be modified by reaction with alkylating agents that bind to the surface of porous silica gel 60. 

Compared with other synthetic intermediates, enolates show a decreased reactivity. The differences in reactivity are most striking in reactions with alkylating agents [1] and epoxides [6]. The reactivities of the various types of enolates towards alkyl halides decrease in the order C=C(0 )NR2 (amide-enolate) C=C(0 )0R (ester enolate) C=CO (ketone-enolate). Metallated nitriles, imines, and S,S-acetals are, in general, much better nucleophiles than enolates in alkylations and ft-hydroxyalkylations [1], Furthermore, the alkylation of aldehyde and ketone enolates usually does not stop after the mono-functionalization [12]. The decreased reactivity of (especially) aldehyde and ketone enolates also appears in thiolations with disulfides [2]. A solution of lithiated cyclohexanone in THF does not react at 20°C with CH3SSCH3 [1,2]. 

Sodium arenesulfinates form aryl alkyl sulfones in PT-catalyzed reactions with alkylating agents (eqs. 141 and 142). 

CHANSRI. 1982. Dianion of diethyl succinate reactions with alkylating agents and carbonyl compounds. Chem. Lett., 687-690. 

Reaction with Alkylating Agents—Ring Expansion of Boron HeterocycUcs... 

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