The efficient and practical nucleophilic cyanation and trifluoromethylation with appropriate trimethylsilyl nucleophiles were developed. Catalytic amounts of cheap and nontoxic Cs 2 CO 3 were used to maintain a sufficiently high concentration of nucleophilic anion (CN − or CF 3 − ) which could begin the catalytic cycle. The present methodologies provide diverse functionalized monofluoroalkenes bearing a cyano and trifluoromethyl group with excellent to moderate stereoselectivities.

A facile method to synthesize 3‐halobenzo‐heterocyclic‐2‐carbonyl compounds is described. Mechanistic studies suggested that a halo‐cyclization process, which generated the unstable spiro‐acetal transition state and readily convertible to the corresponding carbonyl compound might be involved. Diverse 3‐halobenzo‐heterocyclic‐2‐carbonyl compounds could be synthesized with up to 95 % yield in mild conditions with inexpensive starting materials.magnified image

Copper-catalyzed nitrene transfer for amination/cyclization of tryptophols and tryptamines to generate the corresponding indole alkaloids in good to excellent yields was successfully developed.

A first example of Fe-catalyzed dearomative amination of b-naphthols with aryl azides is described. The method constructs a nitrogen-containing quaternary carbon center catalyzed by cheap and readily available iron salt FeCl 2 , and affords a series of a-amino-b-naphthalenones in good to excellent yields under simple and mild reaction conditions. Preliminary experimental and computational studies suggest that the reaction is probably initiated by iron-iminyl diradical and followed by intramolecular hydrogen transfer to generate iron-aminyl radical and finally an intramolecular radical combination reaction.Nitrogen is one of the most important elements in natural products and bioactive compounds. Thus, many efforts have been put into the development of efficient synthetic approaches to nitrogen-containing organic compounds. Among them, transition-metalcatalyzed nitrene transfer reaction with azides as precursors is regarded as one of the most efficient and atom-economic tools for the synthesis of nitrogencontaining moleculars. [1] However, only a few kind of efficient nitrene transfer reactions such as CÀH bond amination, [2] aziridination of olefins, [3] and sulfur imidations [4] were developed (Scheme 1). Hence, exploring the applications of such reactions in other type of transformations to overcome some difficult targets like constructing of nitrogen-containing quaternary carbon center [5] is an interesting but still challenging objective.Generally, in first row transition metal catalyzed nitrene transfer reactions, metal imido species, proved as the key active intermediate, has been confirmed to have significant radical character. [6][7][8] For instance, recent advances in the iron-catalyzed C-H amination reaction [7, 8] have demonstrated that the mechanism involves a hydrogen atom abstraction (HAA) from C-H bonds by iron-imido species followed by radical rebound [9] to the iron-amido moiety on basis of a number of theoretical and experimental evidences. We postulated that if a metal imido species abstracts a hydrogen from OÀH bond of enolate to form an enolate radical which could isomer to a-carbonyl radical, [10] the a-carbonyl radical could couple with the newly formed iron-aminyl radical, and would therefore offer a valuable method for constructing CÀN bond. Herein, we report the first successful example Scheme 1. The types of metal catalyzed nitrene transfer reactions.

CC bond breaking to access the CN bond remains an underdeveloped area. A new protocol for CC bond cleavage of alkenes under nonoxidative conditions to produce imines via an iron-catalyzed nitrene transfer reaction of 4-hydroxystilbenes with aryl azides is reported. The success of various sequential one-pot reactions reveals that the good compatibility of this method makes it very attractive for synthetic applications. On the basis of experimental observations, a plausible reaction mechanism is also proposed.