Letters in Organic Chemistry - Volume 17, Issue 11, 2020

A novel series of 5-(benzo[d]thiazol-2-yl)benzo[d]oxazole-based compounds was synthesized in four linear steps in high yield from vanillin. Both benzo[d]thiazole and benzo[d]oxazole cyclizations were assisted with a domestic microwave oven in about 4-8 minutes in which the yield of the benzo[d]oxazole cyclization was up to 92%. Structures of the new synthesized compounds were elucidated by spectral data.

The micellar catalysis is well-known for its hydrophobic effect that is the tendency of nonpolar groups to cluster within the lipophilic core so as to shield them from contact with an aqueous environment formed upon the dissolution of a surfactant in water. This provides a unique opportunity to establish organic transformations in greener solvents, such as water leading to organic waste control and easy product isolation protoco Read More

A simple and appropriate procedure for the synthesis of quinazoline-2,4(1H,3H)-dione derivatives from isocyanides, aniline and isocyanate via the Cu-catalyzed intramolecular C-H activation reaction is reported. The advantages of this method are one-pot conditions, accessible starting materials- catalyst, high yield of products, and short reaction times. The structures are confirmed spectroscopically (1H- and 13C-NMR, I Read More

A bifunctional squaramide catalyzed the enantioselective Michael addition of pyrazol-3- ones to ortho-quinone methides, generated in situ from 2-(1-tosylalkyl)phenols is presented. The corresponding chiral pyrazolones are obtained with good to excellent yields (27-98%) and enantiomeric excess (14-99% ee).

A method for gram scale preparation of 2-fluoropropionyl-carfentanil was established, starting from 4-phenylamino-1-benzyl-4-piperidinecarboxylic acid. 2-Fluoropropionyl-carfentanil carboxylic acid and 2-chloropropionyl-carfentanil as precursors were synthesized for the radiosynthesis of 11C and/or 18F labelled 2-fluoropropionyl-carfentanil derivatives via two separate reaction routes. Conformational analysis of 2-fluoropropio Read More

A convenient and efficient chiral CuFe2O4@SiO2-Mn(III) Ch.salen nanocatalyst has been developed for the C-N cross-coupling reactions of aryl halides/ phenylboronic acid with N-heterocyclic compounds in water and/or DMSO under mild conditions. The catalyst could be applied for the N-arylation of a variety of nitrogen-containing heterocycles with aryl chlorides, bromides, iodides and phenylboronic acid under mild condit Read More

We have synthesized a library of new 1,2,3-triazole incorporated 1,3,4-thiadiazoleisothiazolo[ 4,3-b]pyridine derivatives 12a-j and have screened these products for their anticancer activities against four human cancer cell lines such as MCF-7 (breast cancer), A549 (lung cancer), DU-145 (prostate cancer), and MDA MB-231 (breast cancer) using MTT assay with etoposide as a positive control. Among them, compound 12e Read More

Glycosyl donors have been experimentally shown to have a high tendency for acyl transfer to the alcohol nucleophile as a major side product during glycosylation reactions. Therefore, a neighbouring group participatory mechanism of glycosylation is explored using D-galactopyranose based donor having 2-O-acyl functionality by employing density functional theory. The reaction proceeds via galactopyranosyl dioxoleniu Read More

A catalyst system derived from commercially available Cu(NO3)2.3H2O and 2,5- dihydroxyterephthalic acid is applied to the homocoupling reaction of arylboronic acids. This transformation provides a convenient approach to symmetrical biaryls with good to excellent yields (39%- 95%), and exhibits good functional group compatibility. Furthermore, biaryl can be prepared in gram quantities in good yield.

For (Z)-(Z)-N-(λ5-phosphanylidene) formohydrazonic formic anhydride, Aza-Wittig reaction and Mumm rearrangement are studied using both density functional and coupled cluster theories. For this purpose, two different products starting from one substrate are considered that are competing with each other. The obtained products, P1 and P2, are thermodynamically favorable. The product of the aza-Wittig reaction, Read More

A simple and efficient methodology for Friedel-Crafts acylation of 3-methylindole using Amberlyst 15 resin as catalyst is described. This methodology shows good selectivity towards the formation of the products of 2-acylation, (3-methyl-1H-indol-2-yl)ketones. Several advantages can be ascribed to Amberlyst 15, among them; are the ease of handling, quick separation from the reaction mixture and minimum or no pro Read More