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Treatment of anti alkyl o-biaryl ketoximes and anti aryl o-biaryl ketoximes with Tf2O at 120 °C, followed by quenching with Et3N gave 6-alkylphenanthridines and 6-arylphenanthridines in good yields, respectively. These reactions proceeded through the O-triflation of the ketoximes, the Beckmann rearrangement, and the electrophilic cyclization of the formed nitrilium group onto the aromatic ring. © 2021 Elsevier Science. All rights reserved.

Alkyl aryl ketones were successfully converted into the corresponding 2,5-disubstituted and 2,4,5-trisubstituted oxazoles in good to moderate yields in a one-pot manner, utilizing iodine, Oxone®, and trifluoromethanesulfonic acid in nitriles under transition-metal-free conditions. The present method could be used for the preparation of Oxaprozin from benzyl phenyl ketone and succinonitrile. A possible reaction mechanism was proposed in which the key intermediates were α-iodoalkyl aryl ketones and α-iodosylalkyl aryl ketones.

Ion-supported Ph 3 P, 4-(diphenylphosphino)benzyltrimethylammonium bromide (IS-Ph 3 P), could be used for the facile amidation of a wide range of carboxylic acids with amines in the presence of bromotrichloromethane to provide the corresponding amides in good yields. In the present reaction, the desired amides were obtained in good yields with high purity by simple extraction of the reaction mixture with diethyl ether or chloroform and subsequent removal of the solvent from the extract. Moreover, ion-supported Ph 3 PO (IS-Ph 3 PO), which was a co-product derived from IS-Ph 3 P in the present reductive condensation, was recovered in high yield and could be reduced to IS-Ph 3 P for reuse in the same amidation of carboxylic acid.

The oxidation of secondary alcohols and primary alcohols with two novel ion-supported (diacetoxyiodo)benzenes (IS-DIBs) A and B in the presence of a catalytic amount of 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) in dichloromethane at room temperature proceeded efficiently to provide the corresponding ketones and aldehydes, respectively, in good yields. The oxidative reaction of N , N -diisopropylbenzylamines with those IS-DIBs was also carried out to generate the corresponding aromatic aldehydes in good yields. In addition, the Hofmann rearrangement of primary amides in methanol under basic conditions and the oxidative 1,2-rearrangement of propiophenones in trimethyl orthoformate under acidic conditions with those IS-DIBs provided the corresponding methyl carbamates and methyl 2-arylpropanoates, respectively, in good yields. Moreover, treatment of acetophenones with those IS-DIBs in the presence of trifluoromethanesulfonic acid in acetonitrile generated the corresponding 5-aryl-2-methyloxazoles in good yields. In those five reactions, the desired products were obtained in good yields with high purity by simple extraction of the reaction mixture with diethyl ether and subsequent removal of the solvent from the extract. Moreover, ion-supported iodobenzenes, which were the co-products derived from IS-DIBs in the present oxidative reactions, were recovered in good yields and could be re-oxidized to IS-DIBs A and B for reuse in the same oxidative reactions.

Various aryl bromides were efficiently converted into the corresponding aromatic nitriles in good yields by the treatment with Mg turnings and subsequently DMF, followed by treatment with molecular iodine and aq NH3. The same treatment of aryl bromides, which are weakly reactive to Mg turnings, with iPrMgCl·LiCl and subsequently DMF, followed by the treatment with molecular iodine and aq NH3 also afforded the corresponding aromatic nitriles in good yields. On the other hand, when N-formylpiperidine was used instead of DMF, p-substituted β-bromostyrenes were converted into the corresponding p-substituted cinnamonitriles, i.e., α,β-unsaturated nitriles, in good to moderate yields by the same procedure. The reactions were carried out by means of a simple experimental procedure and did not require any toxic metal cyanides or expensive rare metals. Therefore, the present reactions are practical and environmentally benign one-pot methods for the preparation of aromatic nitriles, cinnamonitriles, and aliphatic nitriles from aryl bromides, β-bromostyrenes, and alkyl bromides, respectively, through the formation of Grignard reagents and their DMF or N-formylpiperidine adducts.

Various diaryl ketones, alkyl aryl ketones, and dialkyl ketones were efficiently prepared in good yields by the reactions of the Grignard reagents derived from aryl or alkyl bromides, followed by the reactions with aromatic or aliphatic aldehydes and the subsequent treatment with 1,3-diiodo-5,5-dimethylhydantoin and K2CO3, in a one-pot method. The same treatment of aromatic bromides bearing electron-withdrawing groups, such as ester, nitrile, ketone, and nitro groups with i-PrMgCl·LiCl or PhMgCl instead of Mg, also provided the corresponding diaryl and alkyl aryl ketones in good yields. The above methods are simple and practical transition-metal-free methods for the preparation of various diaryl ketones and alkyl aryl ketones bearing electron-rich aromatic groups and electron-deficient aromatic groups, as well as dialkyl ketones.

The Swern oxidation of various benzylic and allylic alcohols, primary alcohols, and secondary alcohols with two ion-supported methyl sulfoxides A-1 ( C 6 ) and B-1 ( C 10 ) , and oxalyl chloride in the presence of triethylamine in dichloromethane, followed by simple diethyl ether extraction of the reaction mixture, gave the corresponding aldehydes and ketones, respectively, in good yields with high purity. Similarly, the Corey–Kim oxidation of various benzylic and allylic alcohols, primary alcohols, and secondary alcohols with two ion-supported methyl sulfides A-2 ( C 6 ) and B-2 ( C 10 ), and N -chlorosuccinimide in the presence of triethylamine in dichloromethane, followed by simple diethyl ether extraction of the reaction mixture, furnished the corresponding aldehydes and ketones, respectively, in good yields with high purity. Both reactions did not produce any unpleasant odor at all. In the Swern oxidation, ion-supported methyl sulfides were recovered in high yields and could be re-oxidized to produce ion-supported methyl sulfoxides A-1 ( C 6 ) and B-1 ( C 10 ), for reuse in the same oxidation. In the Corey–Kim oxidation, ion-supported methyl sulfides A-2 ( C 6 ) and B-2 ( C 10 ) were recovered in high yields and could be also reused for the same oxidation.

Various electron-rich aromatics could be efficiently transformed into the corresponding aromatic nitriles in good to moderate yields by treatment with DMF and POCl 3 , followed by the reaction with molecular iodine or 1,3-diiodo-5,5-dimethylhydantoin (DIH) in aq NH 3 . Some of less reactive aromatics, such as anisole, 1,2-dimethoxybenzene, 1,4-dimethoxybenzene, and mesityrene, could be also transformed into the corresponding aromatic nitriles in good to moderate yields using N -methylformanilide and O(POCl 2 ) 2 , followed by the reaction with molecular iodine in aq NH 3 . Moreover, propiophenone derivatives could be successfully transformed into the corresponding β-chlorocinnamonitriles by the reaction with DMF and POCl 3 , followed by the reaction with molecular iodine and aq NH 3 . These reactions are novel metal-free one-pot methods for the preparation of aromatic nitriles from electron-rich aromatics and β-chlorocinnamonitriles from propiophenones.

Various aromatic bromides were treated with n -BuLi and subsequently with ethyl formate, followed by the reaction with ethanol and molecular iodine in the presence of K 2 CO 3 to provide the corresponding aromatic ethyl esters in good yields. Moreover, aromatic bromides could be transformed into the corresponding aromatic methyl esters in good yields by the treatment with n -BuLi and subsequently with DMF, followed by the reaction with methanol, molecular iodine, and K 2 CO 3 . Some aromatics could be also converted into the corresponding aromatic esters in good yields by the treatment with n -BuLi, and subsequently with ethyl formate or DMF, followed by the reaction with molecular iodine and K 2 CO 3 . The present reactions offer a novel route for the transition-metal-free, carbon-monoxide-free, and therefore environmentally benign one-pot conversion of aromatic bromides and aromatics into aromatic esters.

Various N-tosyl arylimines reacted with methyl vinyl ketone and ethyl vinyl ketone in the presence of ion-supported Ph3P A and B to give adducts, N-(2′-methylene-3′-oxo-1′-arylbutyl)-4-methylbenzenesulfonamides and N-(2′-methylene-3′-oxo-1′-arylpentyl)-4-methylbenzenesulfonamides, respectively, in good yields with high purity by simple diethyl ether extraction of the reaction mixture. Moreover, ion-supported Ph3P A and B could be repeatedly used for the same reaction to provide the corresponding adducts while maintaining good yields with high purity.

Aromatic ketones were efficiently prepared in good yields by the reactions of aryl bromides with n-BuLi, followed by the reactions with aromatic aldehydes or aliphatic aldehydes and the subsequent treatment with molecular iodine and K2CO3, in a one-pot method. The same treatment of arenes, instead of aromatic bromides, also provided the corresponding aromatic ketones in good yields. Using these methods, various diaryl ketones and alkyl aryl ketones bearing electron-rich aromatics and electron-deficient aromatics could be prepared efficiently by a simple, transition-metal-free, and therefore environmentally benign experimental procedure.

Various esters were efficiently converted into the corresponding nitriles in good yields by the treatment with sodium diisobutyl-tert-butoxyaluminium hydride (SDBBA-H), followed by treatment with molecular iodine in aq ammonia. The present one-pot method is very efficient and practical for the conversion of various aromatic and aliphatic esters into the corresponding nitriles.

Various N , N -dimethyl amides, N -methoxy- N -methyl amides, and isopropyl esters were smoothly transformed into the corresponding nitriles in good to moderate yields by the treatment with diisobutylaluminium hydride, followed by treatment with molecular iodine in aq ammonia. The present reactions are novel one-pot and practical methods for the transformation of N , N -disubstituted amides and isopropyl esters into nitriles, through the formation of hemiaminal O -AlBu 2 and hemiacetal O -AlBu 2 , respectively.

Various aromatic bromides and iodides were smoothly converted into the corresponding aromatic nitriles in good to moderate yields by the treatment with n-butyllithium and subsequently DMF, followed by treatment with molecular iodine in aq NH3. The same treatment of typical aromatics and heteroaromatics with n-butyllithium and subsequently DMF, followed by treatment with molecular iodine in aq NH3 also provided the corresponding aromatic nitriles in good yields. Moreover, the same treatment of aromatic bromides and aromatics with half amount of DIH (1,3-diiodo-5,5-dimethylhydantoin) instead of molecular iodine worked effectively to give the corresponding aromatic nitriles, respectively, in good yields. These reactions are novel and environmentally benign one-pot methods for the preparation of aromatic nitriles from aromatic bromides and aromatics, respectively, through the formation of aryllithiums and their DMF adducts.