Showing papers on "Alkylation published in 1981"
TL;DR: In this paper, the primary and secondary alcohols effect alkylation of primary amines in the presence of rhodium, iridium, and ruthenium compounds at ⩽ 100 °C.
Abstract: Primary and secondary alcohols effect alkylation of primary and secondary amines in the presence of rhodium, iridium, and ruthenium compounds at ⩽ 100 °C, whereby selective monoalkylation of primary amines can be achieved and heterocyclic rings can be constructed by both inter- and intra-molecular processes.
351 citations
TL;DR: Aniline reacts with saturated and 2,3-unsaturated alcohols in the presence of ruthenium catalyst at 180°C to give N-alkylanilines and 2-3-alkylquinolines in good yields as discussed by the authors.
286 citations
147 citations
TL;DR: In this article, a new silicon-based protecting group for primary amines has been developed, and its usefulness is illustrated in a simple synthesis of an alkylated amino acid derivative.
125 citations
105 citations
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65 citations
TL;DR: In this paper, it was found that on the H-ZSM-5 steamed at 950°C and on H-Y catalyst both o-and p-xylene were the primary products at 400°C.
Abstract: The reaction in the title was studied at 300–700°C. It was found that on the H-ZSM-5 steamed at 950°C and the H-ZSM-5 loaded with MgO at more than 16wt% catalysts, p-xylene was formed in higher selectivity than 80%. It was also found that the primary product in this alkylation was only p-xylene on H-ZSM-5 catalyst, while on H-Y catalyst both of o- and p-xylene were the primary products at 400°C. In order to form p-xylene selectively, the strong acid sites must be reduced for the suppression of the isomerization of p-xylene produced preferentially and the active sites on the outer surface of the zeolite must be killed for making the reaction proceed only in the pore.
64 citations
TL;DR: Conjugate addition, followed by alkylation, bromination and desilyl-bromination made the β-silylketone (4 ) an a 3 d 3 -synthon (5 ) and the β -silylynone (6 ) a 2a 3d 3 -symbol (7).
63 citations
TL;DR: Acylsilanes undergo efficient protodesilylation upon treatment with fluoride ion in moist DMSO, HMPT, or THF as mentioned in this paper, but not by chloride ion or bromide ion.
Journal Article•
TL;DR: In this article, the adsorption of ethylene and its conversion to hydrocarbons on zeolite H-ZSM-5 as catalyst was investigated by 13C NMR.
TL;DR: Several new multi-step methods for the synthesis of α-keto esters have been reported recently which are based on the addition of alkyl lithium reagents to triethoxyacetonitrile.
TL;DR: Methyl bromide was studied in a forward mutation system of E. coli to evaluate the relationship between dose and mutagenic response and the degree of alkylation of hemoglobin and from the relative reactivities of DNA and hemoglobin towards methyl bromides in vitro was considerably lower than expected.
Abstract: Methyl bromide was studied in a forward mutation system of E. coli to evaluate the relationship between dose and mutagenic response. The compound had a high toxicity and a low mutagenic efficiency, as expected from the high s value. The mutagenic effectiveness was estimated to be 1 mutation per 10 8 surviving bacteria per mM·h, in reasonable agreement with expectation from reaction kinetic data. To study the possibilities of using hemoglobin alkylation for an estimation of DNA alkylation in vivo, mice were treated with 14 C-labeled methyl bromide. The degree of alkylation of DNA, determined in liver and spleen, was considerably lower than expected (200 and 20 times, respectively) from the degree of alkylation of hemoglobin and from the relative reactivities of DNA and hemoglobin towards methyl bromide in vitro. When hemoglobin alkylation is used for quantitative risk estimations, a correction factor has to be applied by taking into account the difference between the dose in red blood cells and the dose in the compartments of DNA.
TL;DR: In this paper, a 5-Alkyl-2-trimethylsilylfurans, easily accessible via successive alkylation and silylation of furan, undergo oxidation cleanly with peracetic acid to afford the corresponding Δ3-butenolides in good yields.
Patent•
15 Jan 1981TL;DR: In this paper, a hydrocarbon feed for use in a catalytic conversion process that utilizes a zeolite catalyst, and that contains a catalytically deleterious impurity, is refined by contact with a zeolitic sorbent.
Abstract: A hydrocarbon feed for use in a catalytic conversion process that utilizes a zeolite catalyst, and that contains a catalytically deleterious impurity, is refined by contact with a zeolitic sorbent. The invention is applicable to dewaxing, with an example illustrating reduction by 100° F. of the initial equilibrium (lineout) temperature by the method of this invention. Other reactions include conversions of aromatic hydrocarbons such as alkylation, isomerization and disproportionation.
Patent•
24 Mar 1981TL;DR: In this paper, a class of zeolites characterized by a silica to alumina mole ratio of at least 12 and a constraint index in the approximate range of greater than about 2 to about 12 were used for selective acid catalyzed reactions involving olefins.
Abstract: Processes are provided for conducting selective acid catalyzed reactions involving olefins. Said catalytic reactions comprise isomerization, alkylation, addition, oligomerization, polymerization, aromatization, cracking and hydrocracking. The useful catalysts of this invention are the acidic forms of a novel class of zeolites characterized by a silica to alumina mole ratio of at least 12 and a constraint index in the approximate range of greater than about 2 to about 12. By utilization of such zeolites, smaller olefins are preferentially reacted when in mixed streams with larger olefins. Further of the such smaller olefins, linear olefins are preferentially reacted when in mixed streams with non-linear olefins and lesser branched olefins are preferentially reacted when in mixed streams with more highly branched olefins. Over the novel catalysts of this invention, para-disubstituted and/or mono-substituted aromatic olefins will react preferentially over ortho- and/or meta-disubstituted or more highly substituted aromatic olefins.
TL;DR: Alumina coated with potassium fluoride promotes smooth N-alkylation of carboxamides, lactams, and other N-heterocycles with alkyl halides or dialkyl sulfate under mild conditions as mentioned in this paper.
Abstract: Alumina coated with potassium fluoride promotes smooth N-alkylation of carboxamides, lactams, and other N-heterocycles with alkyl halides or dialkyl sulfate under mild conditions.
TL;DR: Keto carbonyl 1,2-and 1,3-transpositions with and without alkylation of the substrate are described together with ketone synthesis from thiocarboxylic S-ester as discussed by the authors.
TL;DR: The O -silylated enolates of ketones, aldehydes, esters, and lactones can be regiospecifically alkylated by 1,5-dithienium fluoroborate to give the selectivity protected β-dicarbonyl compounds as discussed by the authors.
TL;DR: In this article, the optically active 6-hydroxyester was converted to 1,5-diketone and regioselective aldolcondensation of the latter furnished (S)- 5 and (S- 6 respectively, each with an e.g.