Recent advances on controllable and selective catalytic oxidation of cyclohexene

Because of multiple potential reaction sites and variable oxidation depths,oxidation of cyclohexene can lead to a mixture of products with different oxidation states and functional groups,such as 7-oxabicyclo[4.1.0]heptane,trans/cis-cyclohexane-1,2-diol,cyclohex-2-en-1-ol,cyclohex-2-en-1-one,and even adipic acid.These products are broadly and abundantly used intermediates in the chemical industry;therefore,controllable oxidation reactions for cyclohexene that can selectively afford the targeted products are synthetically valuable for applications in both the academy and industry,thus becoming the aim of synthetic and catalytic chemists in the field.Many reports on selective oxidation of cyclohexene have recently appeared in the literature because of its significance.This short review summarizes the recent advances on this subject,and the contents are mainly classified based on the chosen oxidants.We hope that this review can provide a useful guide for controllable and selective catalytic oxidation of cyclohexene for interested readers from both the academy and industry.

Synthesis of selenium-doped carbon from glucose:An efficient antibacterial material against Xcc

Se/C as a novel carbon-based biomaterial was prepared by using cheap and abundant glucose as the carbon source.It was highly active and could well restrain Xanthomonas campestris pv.campestris(EC50=4.7403 μg/mL),a very harmful germ causing the devastating cabbage black rot disease and resulting in huge economic losses.As a type of carbon material insoluble in wate r,Se/C is bio-compatible and can adhere onto the leaves of the plants to allow a slow and sustained release of its efficacy,affording an efficient method for the cabbage black rot disease prevention and cure.This work as the first report on the bioactivity studies of Se/C significantly expands the application scopes of the selenium-containing materials and may draw continuous attentions from a broad field.

Diverse synthesis of the C ring fragment of bryostatins via Zn/Cu-promoted conjugate addition of α-hydroxy iodide with enone

A convergent approach to 1,5-hydroxy ketones,the general precursors for constructing the C ring of bryostatins,has been developed via a Zn/Cu-promoted conjugate addition of a-hydroxy iodides with enones.The reaction leads to direct formation of the C21-C22 bond and tolerates diverse functionalities at the C17-,C18-and C24-positions.The approach also enables a more concise synthesis of the known C ring intermediate(10 longest linear steps and 14 total steps),in contrast to its previous synthesis(17 longest linear steps and 22 total steps) in our total synthesis of bryostatin 8.