Ring-Opening Reaction of Imidazo[1,2-a]pyridines Using (Diacetoxyiodo)benzene and NaN3: The Synthesis of α-Iminonitriles

Phenyliodine(III)diacetate (PIDA): Applications in Organic Synthesis

One of the hypervalent iodines most widely used as an oxidizing agent in organic chemistry is (diacetoxyiodo)benzene (PhI(OAc)2), also known as (DAIB), phenyliodine(III) diacetate (PIDA). In this septennial mini-review, the authors have concisely and systematically presented representative applications of PIDA in organic synthesis involving C-H functionalization, hetero-hetero bond formations, heterocyclic ring construction, rearrangements or migrations and miscellaneous reactions along with their interesting mechanistic aspects starting from the summer of 2015 to the present.

Cellulose-Supported Sulfonated Magnetic Nanoparticles: Utilized for One-pot Synthesis of α-Iminonitrile Derivatives

ntroduction: An instrumental strategy for α-iminonitrile derivatives preparation by Fe3O4@cellulose-OSO3H (MCSA) as an eco-friendly nanocatalyst and oxidative agent in aerobic condition, is presented.

MATERIALS AND METHODS

Through this method, a one-pot three-component condensation reaction of various aldehydes, primary amines and trimethylsilylcyanide (TMSCN) were applied to synthesize the desired products. It was performed in absolute ethanol and under a mild condition by using the presented nanocatalyst. High reaction yields were obtained through using the presented magnetic agent, as well. Moreover, the threecomponent reactions were executed using accessible and economical precursors. The convenient separation and recyclability of the used nanocatalyst were also precisely investigated.

RESULTS AND DISCUSSION

In this research, we identified novel α-iminonitrile derivatives using 1H NMR, 13C NMR, CHN, and FT-IR analyses, as well. In order to determine the well-known derivatives, we used FT-IR method as well as comparing their melting points with those of reported.

CONCLUSION

In summary, an extremely efficient method was used for the environmentally-friendly synthesis of α-iminonitrile derivatives that are important bioactive substances. The catalytic oxidative coupling reaction afforded the products via a one-pot three-component condensation reaction of various aldehydes, primary amines and TMSCN with great reaction yields, in ethanol under mild conditions.

A facile tandem decyanation/cyanation reaction of α-iminonitriles toward cyano-substituted amides

A new tandem decyanation/cyanation reaction of α-iminonitriles has been developed. A variety of cyano-substituted aryl amides and heteroaryl amides are synthesized in good yields. Both electron-rich and electron-deficient groups are compatible with the standard conditions. This reaction features a nonmetallic cyano source, tandem decyanation and cyanation reaction, waste utilization of the HCN from the hydrolysis of α-iminonitriles, formation of two important functional groups in one-step operation, etc.

Cyanide-Free Ce(III)-Catalyzed Highly Efficient Synthesis of α-Iminonitriles from 2-Aminopyridines and Nitroalkenes via Intermolecular Dehydration Reaction

A direct and rapid method for the synthesis of α-iminonitriles achieved good to excellent yields. A novel intermolecular dehydration reaction between 2-aminopyridines and nitroalkenes is reported via a rare-earth-metal catalyst. The merits of this transformation include cyanide-free protocol, short reaction time, simple operation, water as the only byproduct, commercially available reagents, good functional group tolerance, etc. Moreover, nitroalkenes are demonstrated as a new "CN" source in this transformation.

(Diacetoxy)iodobenzene-Mediated Regioselective Imidation of Imidazoheterocycles with N-Fluorobenzenesulfonimide

Metal-free (diacetoxy)iodobenzene-mediated regioselective imidation of imidazoheterocycles using commercially available N-fluorobenzenesulfonimide as an imidating reagent has been developed. This protocol exhibits broad substrate scope with good to excellent yields of the imidated imidazopyridines under mild conditions in short reaction times. The present protocol also represents an efficient way to access the imidated derivatives of imidazo[2,1-b]thiazole, benzo[d]imidazo-[2,1-b]thiazole, indoles, and indolizines. A radical mechanistic pathway has been proposed for the present protocol.