NAFION-H CATALYZED CONDENSATION OF ACETOPHENONE DERIVATIVES: A PREPARATIVE ROUTE OF 1,3,5-TRIARYLBENZENES

Cyanide is a highly toxic anion and poison to the environment. Therefore, fast, effective, and efficient analysis methods to detect cyanide are needed. Herein, symmetrical chemosensor of 2’-hydroxy acetophenone azine (1) and 2’,4’-dihydroxy acetophenone azine (2) has been synthesized tested as colorimetric and fluorescent cyanide chemosensor. The azines were produced from the condensation of acetophenone derivatives with hydrazine hydrate in ethanol under reflux or ultrasonic irradiation methods. Colorimetric and fluorescent chemosensor tests showed selectivity to acetate and cyanide anions in DMSO. The limit of detection (LOD) for colorimetric measurement of cyanide anion was 9.68×10–4 M for compound (1) and 9.63×10–5 M for compound (2), while the fluorescent method showed 15.90×10–4 M for compound (1) and 8.95×10–5 M for compound (2), respectively. In addition, test paper-strips containing sensor 2 indicated noticeable results for 'naked eye' detection of cyanide in an aqueous medium.

Download Full-text

l-Prolinal Dithioacetal: A Highly Effective Organocatalyst for the Direct Nitro-Michael Addition to Selected Cyclic and Aromatic Ketones

Synthesis ◽

10.1055/s-0037-1611531 ◽

2019 ◽

Vol 51 (17) ◽

pp. 3356-3368

Author(s):

Piotr Pomarański ◽

Zbigniew Czarnocki

Keyword(s):

Michael Addition ◽

Ring Size ◽

Cyclic Ketones ◽

Asymmetric Syntheses ◽

Aromatic Ketones ◽

Ring Systems ◽

Effective Catalyst ◽

Acetophenone Derivatives ◽

Highly Effective ◽

Related Compounds

The synthesis of novel l-prolinal dithioacetal and its application as an organocatalyst for the direct Michael addition of cyclic ketones and acetophenone derivatives to trans-β-nitrostyrene and related compounds is described. The prolinal dithioacetal acts as effective catalyst in the case of cyclic ketones of different ring size, in particular five- and six-membered examples, as well as larger and smaller ring systems. High enantioselectivity and diastereoselectivity is observed for different substrates and trans-β-nitrostyrenes. Also, the first asymmetric syntheses of selected 2-methyl-4-nitro-1,3-diphenylbutan-1-one derivatives by application of the obtained organocatalyst is presented.

Download Full-text

Design of Iridium N-Heterocyclic Carbene Amino Acid Catalysts for Asymmetric Transfer Hydrogenation of Aryl Ketones

Catalysts ◽

10.3390/catal11060671 ◽

2021 ◽

Vol 11 (6) ◽

pp. 671

Author(s):

Chad M. Bernier ◽

Joseph S. Merola

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Enantiomeric Excess ◽

Transfer Hydrogenation ◽

Acid Catalysts ◽

Asymmetric Transfer Hydrogenation ◽

Reaction Conditions ◽

Chiral Complexes ◽

Acetophenone Derivatives ◽

Aryl Ketones

A series of chiral complexes of the form Ir(NHC)2(aa)(H)(X) (NHC = N-heterocyclic carbene, aa = chelated amino acid, X = halide) was synthesized by oxidative addition of -amino acids to iridium(I) bis-NHC compounds and screened for asymmetric transfer hydrogenation of ketones. Following optimization of the reaction conditions, NHC, and amino acid ligands, high enantioselectivity was achieved when employing the Ir(IMe)2(l-Pro)(H)(I) catalyst (IMe = 1,3-dimethylimidazol-2-ylidene), which asymmetrically reduces a range of acetophenone derivatives in up to 95% enantiomeric excess.

Download Full-text