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    The alkylation of 2-phenyl-4-quinolones was investigated and showed that the N-alkylation versus O-alkylation is highly dependent on whether C-5 is hydroxylated or not. N-Alkylation is favoured by the presence of a 5-hydroxyl group. The synthetic and the NMR structural studies are reported.
    Citations (36)
    Abstract Alkylation of Cyclopropyl Ketones Reduction and Alkylation of α‐Substituted Ketones Substitutive Alkylation of α‐Halocarbonyl Compounds Substitutive Alkylation of β‐Halocarbonyl Compounds Substitutive Alkylation of α‐Diazocarbonyl Compounds Decarboxylation–Allylation of β‐Keto Acids and Esters
    Decarboxylation
    The syntheses of 4a-(3-chloropropyl)- (22), 4a-(3-iodopropyl)- (23), and 4a-mesyloxymethyl-4,4a,5,6,7,8-hexahydro-2(3H)-naphthalenone (24) are described. The results obtained from the intramolecular alkylation of each of these compounds under a variety of experimental conditions are summarized in Tables 1 and 2. It was found that alkylative cyclization of compounds 22 and 23 gave varying amounts of two products, one (34) resulting from α′ alkylation and the other (35) being derived from α alkylation. In contrast, intramolecular alkylation of the enone 24 produced only the γ alkylation product 11, or afforded a mixture of 11 and the α alkylation product 41. The intramolecular alkylation results are discussed in terms of Scheme 5.
    Citations (8)
    A method is presented to measure the alkylation of phosphates in DNA after a treatment with an alkylating agent. Using this method, we have shown that phosphate alkylation represents 15% of total alkylation when DNA is alkylated with ethyl methanesulfonate and only 1% of total alkylation when DNA is alkylated with methyl methanesulfonate. Experiments are also presented which show that phosphate triesters resulting from the alkylation of DNA by ethyl methanesulfonate are very stable, most of them remaining intact after heating at 100°C for 90 min at pH 7.0.
    Methyl methanesulfonate
    Ethyl methanesulfonate
    Dimethyl sulfate
    Kinetics of DNA alkylation with 2',3'-o-[N-2-chloroethyl-N-methylamino)benzylidene]uridine (UCHRCL), uridine-5'-methylphosphate (MepUCHRCL) and 4-(N-2-chloroethyl-N-methylamino)benzylamine (NH2CH2RCl) and kinetics of elimination of alkylated bases have been studied. Efficiency of DNA alkylation (p/s-ratio of rate constant of alkylation to the sum of rate constants of by-reactions of an active intermediate formed from the reagent) increases with an increase of the positive charge of the reagents as well as efficiency of tRNA alkylation. Alkylated bases are eliminated from DNA; rate of elimination depends on the structure of the reagent; it decreases in the series NH2CH2R- greater than greater than UCHR-greater than MepUCHR-. Bases alkylated by NH2CH2RCl and UCHRCl are eliminated from DNA during alkylation; therefore plots of DNA alkylation by NH2CH2RCl have a maximum. DNA alkylated by MepUCHRCl is rather stable; alkylated bases are not eliminated during alkylation. Effect of temperature and pH on elimination has been studied.
    Citations (1)
    Alkylation is the transfer of an alkyl group (CnH2n+1) from one molecule (alkylating agent) to another where it can attach typically to carbon (C-alkylation), but also to oxygen (O-alkylation), nitrogen (N-alkylation), sulfur (S-alkylation) and phosphorous (P-alkylation) depending on the reaction conditions. This chapter discusses the importance of alkylation reactions, then looks at green improvements made by using solid acid catalysts, ionic liquids in Friedel–Crafts reactions, the atom economic borrowing hydrogen strategy and directed alkylation of C–H bonds using alkenes.
    Abstract Ethyl 4,4,4‐trifluoroacetoacetate (I) reacts with the alkyl halides (II) to give the C‐alkylation products (III) and (IV), together with the enol ethers (V).
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    Abstract KF/Al2O3 efficiently catalyzes N‐alkylation of heterocyclic, primary, and secondary amines and S‐alkylation of thiols with a variety of alkyl halides. The N‐alkylation and S‐alkylation adducts were produced in good to excellent yields and in short times.
    Primary (astronomy)
    Citations (22)