First single electron transfer reaction on propargylic chloride in 5-nitroimidazole series

Copper-Catalyzed Propargylation of Nitroalkanes

Using a commercially available, inexpensive, and abundant copper catalyst system, an efficient α-functionalization of nitroalkanes with propargyl bromides is now established. This mild and robust method is highly functional group tolerant and provides straightforward access to complex secondary and tertiary homopropargylic nitroalkanes. Moreover, the utility of these α-propargylated nitroalkanes is demonstrated through downstream functionalization to biologically relevant, five-membered N-heterocycles such as pyrroles and 2-pyrrolines.

An Efficient One-Pot Catalyzed Synthesis of 2,4-Disubstituted 5-Nitroimidazoles Displaying Antiparasitic and Antibacterial Activities

A one-pot regioselective bis-Suzuki-Miyaura or Suzuki-Miyaura/Sonogashira reaction on 2,4-dibromo-1-methyl-5-nitro-1H-imidazole under microwave heating was developed. This method is applicable to a wide range of (hetero)arylboronic acids and terminal alkynes. Additionally, this approach provides a simple and efficient way to synthesize 2,4-disubstituted 5-nitroimidazole derivatives with antibacterial and antiparasitic properties.

Ethyl 2-(2-methyl-4-nitro-1H-imidazol-1-yl)acetate

In the title compound, C8H11N3O4, the imidazole ring and the nitro group are nearly coplanar, with the largest deviation from the mean plane being 0.119 (2) Å. The mean plane through the acetate group is approximately perpendicular to the imidazole ring, subtending a dihedral angle of 75.71 (13)°. In the crystal, molecules are linked by weak C—H...O and very weak C—H...N hydrogen bonds, forming a three-dimensional network. There is also a weak C—H...π(imidazole) interaction, which contributes to the stability of the crystal packing arrangement.

Oxazoles for click chemistry II: synthesis of extended heterocyclic scaffolds

New routes to 2, 4, 5-trisubstituted oxazoles were established whereby the substitution pattern was established by the structure of the starting nonsymmetrical acyloins. 2-Chloromethyl-4, 5-disubstituted oxazoles were prepared by refinements of an earlier described process whereby chloroacetyl esters of symmetrical and non-symmetrical acyloins were cyclized using an ammonium acetate/acetic acid protocol. After substitution is effected, the azide moiety is then installed by substitution under mild conditions. While dibrominated and iodinated phenyloxazoles are required for further synthetic elaboration, the cyclization reaction was found to be very sensitive to the relative positions of the halogens in the starting materials.