Conversion of Aryl Aldehydes to Benzyl Iodides and Diarylmethanes by H₃PO₃/I₂

Abstract

For the first time, H 3 PO 3 was used as both the reducing reagent and the promotor in the reductive benzylation reactions with aryl aldehydes. By using a H 3 PO 3 /I 2 combination, various aromatic aldehydes underwent iodination reactions and Friedel−Crafts type reactions with arenes via benzyl iodide intermediates, readily producing benzyl iodides and diarylmethanes in good yields. Intramolecular cyclization reactions also took place, giving the corresponding cyclic compounds. This new strategy features easy-handling, low-cost, and metal-free conditions.

Cobalt-Catalyzed Kumada Coupling Forming Sterically Encumbered C–C Bonds

“…Spectra and characterization of products 1 , 3 , 4 – 6 , 9 – 13 , 15 , 19 – 21 , 24 , and 25 matched previously reported values. ,− …”

“…Performance also suffered for tertiary alkyl halides such as tert-butylbromide (20) and the secondary halide 1-(bromoethyl)benzene (19), though the latter case may be due in part to susceptibility of the substrate to undergo radical side reactions. Reaction of MesMgBr with 1,2-dibromoethane resulted in only trace production of monocoupled 2-(2bromoethyl)-mesitylene (22), and no evidence was found for two successive arylations at one substrate. Further investigations on dihalogenated substrates were not conducted.…”

Deoxygenative Functionalizations of Aldehydes, Ketones and Carboxylic Acids

“…[8] Mechanistically,t he Lewis acidic Fe catalyst activates not only the carbonyl for the initial hydrosilylation but also the silyl ether intermediate for the subsequent chlorinative displacement. With similar hydrohalogenation manifolds,benzyl bromide (4.3)and iodide [9] (4.4)could also be delivered at room temperature.…”

Esters as Both Alkylating and Acylating Reagents: PCl3‐Promoted Friedel‐Crafts Reaction in One‐Pot

“…Inspired by a handful of literatures [13][14][15] and our previous work [16] on the reductive alkylation reactions using aromatic aldehydes, we envisioned that the starting material containing both a aldehyde group and an ester group on the benzene ring may undergo the alkylation and acylation process in onepot. This is indeed the case.…”