Manganese-Catalyzed Ring-Opening C—C Bond Fluorination of Cyclobutanols

Manganese-catalyzed C—C bond cleavage of cyclobutanols has attracted great attention due to the high abundance and cheap and eco-friendly behaviour.A manganese-catalyzed ring-opening C—C bond fluorination of cyclobutanols is reported.Under mild conditions,the reaction provides a straightforward access to γ-fluorinated ketones using 10 mol% Mn(OAc)_(2) as catalyst and electrophilic fluorination reagent,which was generated in situ from HF·Et 3N and PhIO,as fluorine source.The reaction has an excellent functional-group tolerance and displays a broad substrate scope,affording the corresponding products in 50%~76%yields.

Ag(I)-Catalyzed Addition of Cyclopropenones and Alcohols via C—C Bond Cleavage

An efficient method for the synthesis of α-phenylcinnamates via silver catalyzed C—C bond activation reaction of cyclopropenone and alcohol was developed.This protocol features a simple reaction system,specific regioselectivity,good functional group compatibility and good yields.It is of great significance for the later modification of natural products.

Recent Advances in Deciphering the Mechanisms and Biological Functions of DNA Demethylation

5-Methylcytosine (5mC) is a dynamic and reversible epigenetic modification in genomic DNA of higher eukaryotes.It has been well-established that the demethylation of 5mC occurs through the ten-eleven translocation (TET)-mediated oxidation of 5mC followed by thymine DNA glycosylase (TDG)-initiated base excision repair (BER).Recent findings also have identified an alternative pathway of DNA demethylation.In this pathway,TET enzymes directly oxidize 5mC to form 5-formylcytosine (5fC) or 5-carboxylcytosine (5caC).These modified bases can undergo direct deformylation or decarboxylation,respectively.Additionally,DNA demethylation can also occur through the deamination of 5mC and 5hmC,resulting in the production of thymine and 5-hydroxymethyluracil (5hmU),respectively.Various DNA demethylation pathways possess critical functional implications and roles in biological processes.This Recent Advances article will focus on the studies of mechanisms and biological functions of DNA demethylation,shedding light on the reversible nature of the epigenetic modification of 5mC.

Recent advances for the photoinduced C—C bond cleavage of cycloketone oximes

Nitriles are widely existed in many bioactive compounds,and they can be easily transformed into other functional groups.Therefore,the synthesis of nitriles under cyanide-free conditions is of significant importance.Recent advances for the synthesis of nitriles through photoinduced C—C bond cleavage of cycloketone oximes classified by the type of C—X bond forming are summarized.Various compounds possessing nitriles can be efficiently accessed via this method.

Asymmetric allylation of aldehydes and alkylation using "carbon-centered" chiral organosilicon compounds

The effects of the chiral substituents attached to silicon on the stereoselectivity of the reactions of C-centered chiral silicon compounds wm examined. The investigation was focused on the asymmetric C—C bond formation reaction of chiral allylsilanes and α-silylallyl anions with aldehydes. The functionalities of the substituents on silicon can be manipulated to improve the stereoselectivities of the reactions remote from silicon atom.