Synthesis of Quaternary Heterocyclic Salts

Abstract

The microwave synthesis of twenty quaternary ammonium salts is described. The syntheses feature comparable yields to conventional synthetic methods reported in the current literature with reduced reaction times and the absence of solvent or minimal solvent.

Solid silica nanoparticles as carriers of fluorescent squaraine dyes in aqueous media: Toward a molecular engineering approach

“…In addition, the possibility to improve the tuning of the process by administering the squaraine-APTS adduct with the co-surfactant has been demonstrated. This is the first report, at the best of our knowledge, on molecular factors ruling the dispersion of squaraines in solid silica nanoparticles, but the number of dye molecules per nanoparticles and likely their photoluminescent fraction are significantly lower with respect what obtained with cyanine dyes [19,21]. Thus, the future steps of this research will be aimed to overcome this gap, targeting brighter hybrid squaraine-SiO2 nanoparticles.…”

“…VG0 and VG1-C2 were prepared as previously described [2]. For the synthesis of SO 3 H-SQ a modified procedure as reported in the literature [2,19]…”

A study on the AMACR catalysed elimination reaction and its application to inhibitor testing

“…The PEGylated fluorescein derivative 32 was synthesised by the method of Zheng et al 42 tert -Butyldimethylsilyl-protected fluorescein 33 was synthesised by the method of Rydzik et al 40 The boronic acid sensor 34 was synthesised by the method described by Sun et al 47 Intermediates 37 , 50 38 , 51 39 , 52 and 40 52 for the synthesis of sensor 35 were produced by known methods. Intermediates 42 53 and 43 53 required for the synthesis of 36 were produced by known methods.…”

10a,11,11-Trimethyl-10a,11-dihydro-8H-benzo[e]imidazo[1,2-a]indol-9(10H)-one

“…Alkylation of 1,1,2-trimethyl-1H-benzo[e]indole with various alkylating agents-such as iodomethane [1], iodoethane [2], 4-iodobutane [3], 1-iodo-3-phenylpropane [4], benzyl bromides [5,6], or 3-iodopropanoic acid [7]-affords the corresponding N-quaternary 1,1,2-trimethyl-1Hbenzo[e]indolium salts. The reactions are usually performed in aprotic solvents such as acetonitrile or toluene with conventional or microwave heating [8]. Upon treatment with various electrophilic counterparts, these salts are converted into dyes, which have found wide application for the development of the near-infrared fluorescent probes [1][2][3][4][5][6][7].…”