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The synthesis of new amino and alkoxy derivatives of thiazole-5-carbaldehyde, on the basis of which α,β-unsaturated ketones of the thiazole series were synthesized, are described in this paper. The possibility of obtaining chalcones and variation of substitution reactions in the thiazole ring has been shown.At the time of its discovery in 1896, chalcone (1,3-diphenylpropen-1-one) [1] interest in the chemistry of its substituted and heterocyclic analogs did not decrease. A retrospective review in Dhar's monograph [2] showed that most attention was concentrated on investigation of the reactivity of the propenone fragment of chalcone. In the reviews [3,4] this was illustrated in examples of the cyclocondensations with 1,2-, 1,3-, and 1,4-dinucleophiles. At the same time reactions with the participation of the aromatic or heterocyclic nuclei were less studied.In the present work we have studied the problem of synthesis of heterocyclic analogs of chalcone with substituents in the heteroaromatic nucleus capable of further transformations not involving the propenone unit. It is known [2, 3] that the most useful method for the synthesis of chalcones is the crotonic condensation with compounds containing formyl and acetyl groups.Starting with this problem we turned our attention to papers [5,6], in which is proposed an original and accessible method for the synthesis of 2,4-dichloro-5-formylthiazole 1. Compound 1 contains at least three reactive centers: two chorine atoms and a formyl group, which is suggested by a series of reactions occurring either at the aldehyde group (reduction, formation of oximes and acetals) [7][8][9], or with participation of the chlorine atoms (substitution reactions with amines and thiols, dehalogenation) [9]. On the other hand, the chemistry of thiazole arouses interest because among its derivatives there are a large number of compounds which possess physiological activity (among natural compounds, for example, the triazole ring is the active center of thiamine, vitamin B 1 ).

Non-agglomerated nanoparticles of an average diameter of 200 nm with a hybrid organicinorganic shell were prepared by reacting the COOH groups of poly(N-dicarbazolyl-lysine)covered silica nanoparticles with zirconium tert-butoxide, Zr(OtBu) 4 , followed by sol-gel processing.

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We report herein the fabrication of a simple and price-affordable portable reaction station for use in parallel solution-phase synthesis. This homemade device uses currently available laboratory components and equipment. Specifically designed to fit standard magnetic hotplates/stirrers, it can simultaneously hold up to 24 heated and magnetically stirred glass reactors of both 10 and 50 mL capacities. Glass reactors are connected by flexible 16-gauge metal needles to a central gas manifold equipped with an inlet/outlet for vacuum and inert gases. Reaction temperatures can be optimally varied from -78 ( composite function)C to 150 degrees C. Using a statistical screening DOE method, this parallel array reactor station has been successfully operated to optimize the one-step deprotective O-formylation of a sterically hindered bis-O-tert-butyldiphenylsilyl (O-TBDPS) aromatic diol. The latter transformation was mediated by the Vilsmeier-Haack reagent POCl3.DMF using a range of Lewis acid and metal salt promoters, including their binary combinations.