An efficient method for the alkylation of α-methylnaphthalene with various alkylating agents using methanesulfonic acid as novel catalysts and solvents

Abstract

Friedel-Crafts alkylations of a-methylnaphthalene with various alkylating agents were first carried out in the presence of methanesulfonic acid (MeSA). The Brønsted acid catalyst MeSA exhibited outstanding catalytic performance, and was found to be excellent catalyst and solvent for alkylation reaction of aromatic hydrocarbon. It's found that alkenes can be used as excellent alkylating agent for alkylation of a-methylnaphthalene. The effects of various reaction parameters like type of alkylating agent, dosages of catalysts, reaction temperature and reaction time were investigated in detail. Moreover, the performance of reuse for catalysts was also studied. It's found that, under the optimal reaction conditions, more than 90% of conversion for olefins and 100% of selectivity for the desired products were obtained. Compared with traditional catalysis technology, the reaction, catalyzed by MeSA catalyst, no volatile solvents needed, good selectivity for desired products could be obtained. The catalyst can be isolated easily from the reaction mixtures by decantation, and was successfully reused. The methanesulfonic acid could be considered as environmentally friendly novel catalyst and solvent for long-chain alkylation of a-methylnaphthalene with alkenes. The catalytic reaction mechanism for alkylation in the presence of MeSA was proposed as well.

Solvent-free tetrahydropyranylation of alcohols catalyzed by amine methanesulfonates

“…Methanesulfonic acid, which is a readily biodegradable and environmentally friendly material [15], has been studied as an acid catalyst in esterification, condensation, and alkylation reactions [16][17][18]. In our study, methanesulfonic acid, used as a tetrahydropyranylation catalyst, has been found, like many strongly acidic catalysts [19], to produce polymeric products of 3,4-dihydro-2H-pyran (DHP).…”

Selective esterification of non-conjugated carboxylic acids in the presence of conjugated or aromatic carboxylic acids over active carbon supported methanesulfonic acid

“…Methanesulfonic acid (MSA) is an important chemical raw material that has recently been widely used in esterification [12,13] , cyclization [14] , alkylation [15] , electrochemistry, etc. In connection with our work on the application of active carbon supported MSA catalysts for the conversion of bioactive natural products, we have recently discovered that the catalyst is efficient for selective esterification of non-conjugated, over conjugated or aromatic carboxylic acids at room temperature (Formula 1).…”

Biomimetic Synthesis and Chemical Proteomics Reveal the Mechanism of Action and Functional Targets of Phloroglucinol Meroterpenoids

“…Initial attempts to reproduce the synthesis of jensenone under prior established conditions failed, resulting in complete decomposition. 58 To mitigate this issue, we conducted the Friedel− Crafts acylation of phloroglucinol with isovaleryl chloride in the presence of methanesulfonic acid as catalyst and solvent, 59 delivering isovalerylphloroglucinol (S1) in 53% yield. This was followed by a modified Duff formylation protocol using formamidine acetate, 60 facilitating the isolation of jensenone in 41% yield without further purification.…”