Palladium-Catalyzed Intramolecular Heck/Aminocarbonylation of Alkene-Tethered Iodobenzenes with Nitro Compounds: Synthesis of Carbamoyl-Substituted Benzoheterocycles.

A palladium-catalyzed intramolecular Heck/aminocarbonylation of alkene-tethered iodobenzenes with nitro compounds has been developed for the synthesis of carbamoyl-substituted benzoheterocycles. Using Mo(CO)6 as a solid CO source, no external reductant or additives were needed in this procedure. Both nitroarenes and nitroalkanes were well tolerated. A range of carbamoyl-substituted dihydrobenzofurans and indolines were prepared in moderate to high yields.

Visible-Light-Induced Carbonylation of Indoles with Phenols under Metal-Free Conditions: Synthesis of Indole-3-carboxylates.

A visible-light-induced carbonylation of indoles with phenols for the synthesis of indole-3-carboxylates has been developed. The reaction proceeded via a radical carbonylation process in which elementary I2 was used as an effective photosensitive initiator and, thus, avoided the use of transition metal catalysts. A series of different aryl indole-3-carboxylates were prepared in moderate to good yields. The broad applicability of this methodology was further highlighted by the late-stage functionalization of several phenol-containing natural products and pharmaceuticals.

Palladium Catalyzed Cascade Azidation/Carbonylation of Aryl Halides with Sodium Azide for the Synthesis of Amides.

Amide synthesis is one of the most important transformations in organic chemistry due to their ubiquitous presence in our daily life. In this communication, a palladium catalyzed cascade azidation/carbonylation of aryl halides for the synthesis of amides was developed. Both iodo- and bromobenzene derivatives were transformed to the corresponding amides using PdCl2 /xantphos as the catalyst system and sodium azide as the nitrogen-source. The reaction proceeds via a cascade azidation/carbonylation process. A range of alkyl and halogen substituted amides were prepared in moderate to good yields.

[Determination of curculigoside in crude medicine Curculigo orchioides by HPLC].

OBJECTIVE: To establish a method for the determination of curculigoside in Curculigo orchioides, a species of crude medicine. METHOD: The methanol was used as the solvent of exatraction and the curculigoside was extracted from the crude medicine with the method of the ultrasonic vibration. Using Sep-Pak C18 cartridges to purify the solution, the curculigoside was detected by HPLC. Intersil ODS-3(150 mm x 4.6 mm, 5 microns) chromatographic column was used, mobile phase of methanol-water-ice acetic acid (45:80:1) and detect wavelength was set at UV 283 nm. RESULT: The average recovery was 99.2% for the determination of curculigoside, RSD = 1.7% (n = 5). The content range of the curculigoside for 6 kinds of different samples was from 0.11% to 0.35%. CONCLUSION: This method could be used to control the quality of crude medicine C. orchioides.