Rapid microwave synthesis

Ziegler J, Merkulov A, Grabolle M, Resch-Genger U, Nann T (2007) High-quality ZnS shells for CdSe nanoparticles rapid microwave synthesis. Langmuir 23 7751-7759... 

Sharma, S., Ganguly, A., Papakonstantinou, R, Miao, X., Li, M., Hutchison, J.L., Delichatsios, M. Ukleja, S. Rapid microwave synthesis of CO tolerant reduced graphene oxide-supported platinum electrocatalysts for oxidation of methanol. J. Phys. Chem. C 114 (2010), pp. 19,459-19,466. 

Tripathi R, Popov G et al (2013) Ultra-rapid microwave synthesis of triplite LiFeS04F. J Mater Chem A 1 2990-2994... 

In a 2006 paper outlining the rapid microwave synthesis of novel cyclic sulfamide HIV-1 protease inhibitors, the aminocarbonylation protocol presented in ref. 17 was applied in the decoration of mono- and bis-aryl bromide containing cyclic sulfamide starting materials [33]. Aniline and benzylamine were used as nucleophiles for the production of two symmetric bis-functionalized and two unsymmetrical monosub-stituted compounds in good yields (59-80%) (Scheme 4.19). Unfortunately, of these anilide or benzylamide containing compounds only one displayed weak HIV-1 protease inhibition [33]. 

Baldassari, S., Komarneni, S., Mariani, E. and Villa, C. (2005) Rapid microwave-hydrothermal synthesis of anatase form of titanium dioxide. Journal of the American Ceramic Society, 88, 3238—3240. 

Nyutu, E.K., Chen, C., Sithambaram, S., Crisostomo, V.M.B. and Suib, S.L. (2008) Systematic control of particle size in rapid open-vessel microwave synthesis of K-OMS-2 nanofibers. Journal of Physical Chemistry C, 112, 6786-6793. 

In a dedicated combinatorial approach, Strohmeier and Kappe have reported the rapid parallel synthesis of polymer-bound enones [33]. This approach involved a two-step protocol utilizing initial high-speed acetoacetylation of Wang resin with a selection of common /i-ketoesters (Scheme 7.13) and subsequent microwave-mediated Knoevenagel condensations with a set of 13 different aldehydes (see Section 7.3.6). 

B. M. Glass, A. P. Combs, Rapid Parallel Synthesis Utilizing Microwave Irradiation Article E0027, Fifth International Electronic Conference on Synthetic Organic Chemistry" (Eds. C. O. Kappe, P. Merino, A. Marzinzik, H. Wennemers, T. Wirth, J. J. Vanden Eynde, S.-K. Lin), CD-ROM edition,... 

The most successful application of microwave energy in the preparation of heterogeneous solid catalysts has been the microwave synthesis and modification of zeolites [21, 22], For example, cracking catalysts in the form of uniformly sized Y zeolite crystallites were prepared by microwave irradiation in 10 min, whereas 10-50 h were required by conventional heating techniques. Similarly, ZSM-5 was synthesized in 30 min by use of this technique. The rapid internal heating induced by microwaves not only led to a shorter synthesis time, and high crystallinity, but also enhanced substitution and ion exchange [22]. 

The palladium-catalyzed Heck carbonylation reaction is a powerful means of generating amides, esters, and carboxylic acids from aryl halides or pseudohalides [28]. The development of rapid, reliable, and convenient procedures for the introduction of carbonyl groups is important for the development of high throughput chemistry in general and high-speed microwave-mediated chemistry in particular. Unfortunately, the traditional method of introducing carbon monoxide into a reaction mixture via a balloon or gas tube is not practical because of the special requirements of microwave synthesis. 

Erdelyi M, Gogoll A (2002) Rapid Microwave-Assisted Solid Phase Peptide Synthesis. Synthesis 1592-1596... 

An efficient synthesis of 2-amino derivatives 256 is depicted in Scheme 70 2-halopyridines are first Ar-alkylated with various halides under microwave activation and next reacted with cyanamide under basic conditions <1999T2317>. A rapid parallel synthesis of derivatives bearing a benzoyl substituent at C-3 based on this reaction has been described <2002SL1544>. 

Microwave Synthesis of Zeolites and Molecular Sieves The use of microwaves holds promise for efficiency improvements in zeolite synthesis due to the rapid heating possible when using microwave radiation [166], The first report of microwave synthesis of zeolites was by Mobil Oil in 1988, which broadly claimed the synthesis of zeolite materials in the presence of a microwave-sympathetic material, such as water or other pro tic component [167]. A number of reports have appeared since, including synthesis of zeolites Y, ZSM-5 [168] and metaUoaluminophosphate-type materials, such as MAPO-5 [169], There have also been extensive investigations in using microwaves for zeoHte membrane synthesis. Recent reviews discuss the progress in microwave zeoHte synthesis [170, 171]. 

Synthesis of the benzopyran ring has also been performed by microwave-assisted copper-catalysed cross coupling of an aryl iodide with terminal alkynes, in the presence of copper(I) iodide/triphenylphosphine (Scheme 3.35)56. An alternative approach involving microwave heating of mixtures of salicylaldehyde and various derivatives of ethyl acetate in the presence of piperidine has enabled rapid Knoevenagel synthesis of coumarin derivatives (Scheme 3.35)57. 

A similar rapid microwave one-pot synthesis of substituted quinazolin-4-ones was also reported, which involved cyclocondensation af anthranilic acid, formic acid (or an orthoester) and an amine under solvent-free conditions (Scheme 3.37)61. A complimentary approach was adopted to synthesise 4-aminoquinazolines in very good yields, involving the reaction of aromatic nitrile compounds with 2-aminobenzonitrile in the presence of a catalytic amount ofbase (Scheme 3.38)62. The reactions were performed in a domestic microwave oven and required only a very short heating time. A microwave-assisted synthesis of a variety of new 3-substituted-2-alkyl-4-(3H)-quinazolinones using isatoic anhydride, 2-aminobenzimidazole and orthoesters has also been described (Scheme 3.38)63. 

Bendale, P.M. and Sun, C.-M., Rapid microwave-assisted liquid-phase combinatorial synthesis of 2-(arylamino)benzimidazoles, /. Comb. Chem., 2002, 4, 359-361. 

Glass, B.M. and Combs, A.P., Case study 4-6 rapid parallel synthesis utilizing microwave irradiation, In Sucholeiki, I. (Ed.), High-Throughput Synthesis. Principles and Practices, Marcel Dekker, New York, 2001, Ch. 4.6, pp. 123-128,... 

Erdelyi, M. and Gogoll, A., Rapid microwave-assisted solid phase peptide synthesis, Synthesis, 2002, 1592-1596. 

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