Modification of Pyrrolo[2,1-a]isoquinolines and Pyrrolo[1,2-a]quinolines with Ammonium Acetate and Dimethyl Sulfoxide via Methylthiomethylation

An efficient methylthiomethylation of pyrroloisoquinolines and pyrroloquinolines has been reached by the use of ammonium acetate and dimethyl sulfoxide. Methylthiomethylated heterocycles can be obtained in moderate to good yields in most cases, while trace amounts to good yields of methylene-bridged products can be observed. Choice of DMSO activator and its amount have a great influence on the chemoselectivity of this process. It is worth noting that this process can also be scalable. Another feature of this process is that the product can be transformed to sulfone and sulfoxide easily.

Mg(OtBu)2-catalyzed C–H oxidation of α-azido arylethanones using TBHP as the oxidant and carbonyl oxygen source: facile access to primary α-ketoamides

A Mg(OtBu)2-catalyzed C(sp3)–H oxidation of α-azido arylethanones to straightforwardly produce primary α-ketoamides is presented.

Formylation and Bromination of Pyrrolo[2,1-a]isoquinoline Derivatives with Bromoisobutyrate and Dimethyl Sulfoxide

We have developed an efficient formylation of pyrroloisoquinolines using bromoisobutyrate and dimethyl sulfoxide as carbonyl reagent. Various formylated pyrroloisoquinolines could be prepared in good yields (up to 94%). This formylation process can be easily scaled up to gram scale with good yield. In most cases of pyrroloisoquinolines without methoxy groups, the combination of bromoisobutyrate and dimethyl sulfoxide could act as a bromination reagent, delivering brominated pyrroloisoquinolines in acceptable to good yields (up to 82%).

I2-DMSO mediated oxidative amidation of methyl ketones with anthranils for the synthesis of α-ketoamides

An I₂-DMSO mediated oxidative amidation of methyl ketones using anthranils as masked N-nucleophiles has been developed for the direct synthesis of α-ketoamides with high atom-economy. This metal-free process involves reductive N-O bond cleavage of anthranils and oxidative C-N bond formation of methyl ketones under mild conditions. The iodo group and electrophilic formyl group provide multiple possibilities for further functionalization of α-ketoamides.

Employing thiocyanate salts as a nitrogen source via CN bond cleavage: divergent synthesis of α-ketoamides and 2-acyloxazoles

A switchable procedure for the synthesis of α-ketoamides and 2-acyloxazoles from aryl methyl ketones and thiocyanate salts is reported.

Metal-Free Oxidative Thioesterification of Methyl Ketones with Thiols/Disulfides for the Synthesis of α-Ketothioesters

A direct C_sp3-H bond oxidative thioesterification of methyl ketones with aromatic thiols/disulfides promoted by TBAI/K₂S₂O₈ has been developed. The reaction provides successfully a simple and efficient method for the synthesis of functionalized α-ketothioesters of aromatic thiols. This practical methodology exhibits readily available starting materials, large-scale applicability, synthetic application, and broad functional group tolerance. A possible mechanism for the transformation is proposed.

The Hydrazine-O2 Redox Couple as a Platform for Organocatalytic Oxidation: Benzo[c]cinnoline-Catalyzed Oxidation of Alkyl Halides to Aldehydes

An organocatalytic oxidation platform that capitalizes on the capacity of hydrazines to undergo rapid autoxidation to diazenes is described. Commercially available benzo[c]cinnoline is shown to catalyze the oxidation of alkyl halides to aldehydes in a novel mechanistic paradigm involving nucleophilic attack, prototropic shift, and hydrolysis. The hydrolysis and reoxidation events occur readily with only adventitious oxygen and water. A survey of the scope of viable substrates is shown along with mechanistic and computational studies that give insight into this mode of catalysis.

Iodine-catalyzed oxidative multiple C–H bond functionalization of isoquinolines with methylarenes: an efficient synthesis of isoquinoline-1,3,4(2H)-triones

An iodine-catalyzed multiple C–H bond functionalization of isoquinolines with methylarenes via a successive benzylic sp³ C–H iodination/N-benzylation/amidation/double sp² C–H oxidation sequence to yield isoquinoline-1,3,4(2H)-triones is developed for the first time.

Transition metal-free synthesis of α-ketoamides from arylmethyl ketones and alkylphosphoramides

Synthesis of α-ketoamides from arylmethyl ketones and hexalkylphosphoramides using TBAI as the catalyst and TBHP as the oxidant.