Copper-catalyzed C-C coupling reaction of aryl iodides with diethylmalonate in toluene at 90°C gave arylated malonates using 5 mol% of CuI with hydrazone 1a as a ligand in good yields under an aerobic atmosphere. We also found CuI/hydrazone 1b in toluene to be an efficient catalytic system for C-O coupling reactions of aryl bromides with phenols to give aryl ethers in good yields at 110°C under an aerobic atmosphere.

Acylation of 1‐methylpyrrole (Ia) and N‐methylimidazole (Ib) with trichloroacetyl chloride (II) yields the ketones (III) which produce a mixture of the isomeric nitroheterocycles (V) and (VI) on treatment with nitric acid (IV).

5-Bromo-2,5-dideoxy-threo-pentono-γ-lactone (III) could be obtained stereoselectively from 3-hydroxy-4-pentenoic acid (I) by the reaction with N-bromosuccinimide in water. On successive treatment with an aqueous potassium hydroxide and an acid type cation exchange resin, bromolactone (III) gave stereoselectively 2-deoxy-erythro-pentono-γ-lactone (IV). Reduction of IV by means of bis(1,2-dimethylpropyl)borane afforded 2-deoxy-erythro-pentose (V). 3-Hydroxy-4-pentenoic acid (I) could be optically resolved. The (+)-acid yielded 2-deoxy-d-erythro-pentose (d-V) and the (−)-acid could be converted to 2-deoxy-l-erythro-pentose (l-V). 2,5-Dideoxy-threo-pentose (VIII) and 5-bromo-2,5-dideoxy-threo-pentose (IX) were obtained from bromo-lactone (III). Diethyl mercaptal of IX gave azido-compound (XI) in a low yield by the reaction with sodium azide. The conformation of γ-lactones (III, IV, and VII) and the mechanistic aspects of stereoselective reactions are discussed.

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