13512-00-0

Upstream product

• 13522-65-1 O-(4-acetamidophenyl) N,N-dimethylcarbamothioate 
• 16958-94-4 sodium 4-acetylaminophenolate 
• 103-90-2 4-acetaminophenol 
• 79-44-7 N,N-Dimethylcarbamoyl chloride 
• 1126-81-4 4-acetamidothiophenol 

Downstream Products

• 1126-81-4 4-acetamidothiophenol 
• 1193-02-8 4-aminotiophenol 

Relevant academic research and scientific papers

Electrochemically Catalyzed Newman-Kwart Rearrangement: Mechanism, Structure-Reactivity Relationship, and Parallels to Photoredox Catalysis

The facilitation of redox-neutral reactions by electrochemical injection of holes and electrons, also known as "electrochemical catalysis", is a little explored approach that has the potential to expand the scope of electrosynthesis immensely. To systematically improve existing protocols and to pave the way toward new developments, a better understanding of the underlying principles is crucial. In this context, we have studied the Newman-Kwart rearrangement of O-arylthiocarbamates to the corresponding S-aryl derivatives, the key step in the synthesis of thiophenols from the corresponding phenols. This transformation is a particularly useful example because the conventional method requires temperatures up to 300 °C, whereas electrochemical catalysis facilitates the reaction at room temperature. A combined experimental-quantum chemical approach revealed several reaction channels and rendered an explanation for the relationship between the structure and reactivity. Furthermore, it is shown how rapid cyclic voltammetry measurements can serve as a tool to predict the feasibility for specific substrates. The study also revealed distinct parallels to photoredox-catalyzed reactions, in which back-electron transfer and chain propagation are competing pathways.

Mechanistic Investigations into the Cation Radical Newman-Kwart Rearrangement

Efforts to elucidate the governing factors in the cation radical Newman-Kwart rearrangement are described. Through a combination of spectroscopic and kinetic analyses, it has been shown that the reactive intermediate is a thione cation radical that has si

Inverting the Selectivity of the Newman-Kwart Rearrangement via One Electron Oxidation at Room Temperature

The discovery that the Newman-Kwart rearrangement can be performed at room temperature by action of a simple and readily available oxidant, cerium ammonium nitrate, is described. The conditions give clean conversion when using electron-rich aromatic subst

An Electrocatalytic Newman-Kwart-type Rearrangement

An electrochemical approach toward rearrangement of O-aryl thiocarbamates to the corresponding S-aryl thiocarbamates is presented. The protocol requires only catalytic amounts of electric charge and allows for operation at room temperature. The electrolys

Ambient-Temperature Newman-Kwart Rearrangement Mediated by Organic Photoredox Catalysis

The Newman-Kwart rearrangement is perhaps the quintessential method for the synthesis of thiophenols from the corresponding phenol. However, the high thermal conditions required for the rearrangement of the requisite O-aryl carbamothioates often leads to decomposition. Herein, we present a general strategy for catalysis of O-aryl carbamothioates to S-aryl carbamothioates using catalytic quantities of a commercially available organic single-electron photooxidant. Importantly, this reaction is facilitated at ambient temperatures.

Thio carbamates and their derivatives

A method is provided for preparing N-acylaminothiophenols, e.g., N-acetyl-para-aminothiophenol, or aminothiophenols, e.g., para-aminothiophenol, or N,S-diacylaminothiophenols, e.g., N,S-diacetyl-para-aminothiophenol, by reacting any of certain sulfur-containing ketones, viz., an S-(acylaryl) N,N-di(organo)thiocarbamate, e.g., S-(4''-acetophenyl)-N,N-dimethylthiocarbamate, an acylthiophenol acylate ester, e.g., 4-acetothiophenol acetate, or a free acylthiophenol, e.g., 4-acetothiophenol with hydroxylamine or a hydroxylamine salt, to form the oxime of the ketone, subjecting the oxime to a Beckmann rearrangement in the presence of a catalyst to form an S-(N-acyl-aminoaryl) N,N-di(organo)thiocarbamate, e.g., S-(N-acetyl-para-aminophenyl) N,N-dimethylthiocarbamate, an N,S-diacylaminothiophenol, e.g., N,S-diacetyl-paraaminothiophenol, or an N-acyl aminothiophenol, e.g., N-acetyl-para-aminothiophenol, respectively. The S-(N-acyl-aminoaryl) N,N-di(organo)thiocarbamate may be hydrolyzed to the N-acyl aminothiophenol or aminothiophenol. The S-(acylaryl) N,N-di(organo)thiocarbamate may be produced by reacting a hydroxy aromatic ketone, e.g., 4-hydroxyacetophenone (4-HAP) with an N,N-di(organo)thiocarbamoyl halide, e.g., N,N-dimethylthiocarbamoyl chloride (DMTC) to form an O-(acylaryl) N,N-di(organo)thiocarbamate, e.g., O-(4''-acetophenyl) N,N-dimethylthiocarbamate, and pyrolytically rearranging the latter compound. The acylthiophenol may be produced by hydrolyzing the S-(acylaryl) N,N-di(organo)thiocarbamate.