Deoxygenative Chlorination of Aldehydes and Alcohols with Dichloromethyl Methyl Ether and TiCl₄

Abstract

Here, we report highly efficient deoxygenative chlorination of aldehydes and alcohols with a dichloromethyl methyl ether and TiCl 4 system. The method converts various aldehydes and alcohols into the desired geminal dichlorides or chlorides with good to excellent yields (up to 99 %). Combined with a subsequent Rieche formylation step using the same reagent system, this method provides an efficient approach for synthesis of aromatic dialdehydes. This strategy involves deoxychlorination of the aryl aldehydes followed by a second formylation of more activated benzal chloride derivatives. Dialdehydes can be easily obtained by hydrolyzing the corresponding of dichloromethyl derivative.

Balancing Lewis Acidity and Carbocation Stability for the Selective Deoxyhalogenation of Aryl Carbonyls and Carbinols

“…This transformation is traditionally completed in multiple steps: often a carbonyl reduction followed by chlorination. Recent procedures have employed BiCl 3 , InCl 3 , GaCl 3 , , FeCl 3 , TiCl 4 , or In­(OH) 3 as Lewis acids in combination with an additional chlorine source, frequently chlorosilanes. This technique has been applied primarily for the conversion of alcohols to chlorides − ,, and less frequently for the conversions of aldehydes, , ketones, or carboxylic acids …”

Synthesis of α-Chloroarylacetic Acid via Electrochemical Carboxylation of α,α-Dichloroarylmethane Derivatives

“…Refs. [38][39][40][41] are cited in Supplementary Materials. Funding: This work has been partially supported by University of Rouen Normandy, INSA Rouen Normandy, the Centre National de la Recherche Scientifique (CNRS), European Regional Development Fund (ERDF), Labex SynOrg (ANR-11-LABX-0029), Carnot Institute I2C, the graduate school for research XL-Chem (ANR-18-EURE-0020 XL CHEM).…”