Linear Selective Hydroformylation of 2‐Arylpropenes Using Water‐Soluble Rh‐PNP Complex: Straightforward Access to 3‐Aryl‐Butyraldehydes

Abstract

Straightforward access to 3‐aryl‐butyraldehydes was developed through the aqueous biphasic Rh‐catalyzed hydroformylation of 2‐arylpropenes using a water‐soluble PNP ligand. This protocol accommodates broad substrate scope with high yields (up to 95 %) and excellent linear selectivity (>99 : 1 b/l ratio). The synthesis of rac‐ar‐turmerone and the gram‐scale hydroformylation further demonstrated the practical nature of this method.

Synthesis and Spectroscopic Characterization of Selected Water-Soluble Ligands Based on 1,10-Phenanthroline Core

“…It was collected by filtration, washed with water, and dried over a vacuum to yield a yellow solid (3.80 g, 86% yield). The crude material obtained was crystallized from methanol to give the following: 2-Methyl-5,7-dinitroquinolin-8-ol as a pale yellow powder 0.45 g (1.8 mmol, 65.0%); 1 H NMR (DMSO-d 6 ; 500.2 MHz) δ = 2.94 (s, 3H, CH 3 ), 8.14 (d, 3 J H,H = 9.0 Hz, 1H, aromatic), 9.21 (s, 1H, aromatic), 9.66 (d, 3 J H,H = 9.0 Hz, 1H, aromatic); 13…”

“…Water-soluble ligands are widely used in various fields, including chemistry, biochemistry, and coordination chemistry. They play a crucial role in many chemical and biological processes and industrial applications, such as hydrogenation and hydrogen production from water [ 1 ], oxidation reactions [ 2 ], and hydroformylation [ 3 , 4 ]. The chemical and physical properties of water-soluble 1,10-phenanthroline derivatives with sulfonate, carboxylic, phosphonic acid, or hydroxylic groups in their constitution have been widely studied and used for the separation of metallic atoms and capillary electrophoresis, as well as for the development of bio-inorganic probes [ 5 ].…”

Recent advancements in the use of Bobbitt's salt and 4-acetamidoTEMPO

“…115 Scheme 50 Babler-Dauben oxidation facilitated by Bobbitt's salt (1). 117 Scheme 51 Oxidation strategy to access blennolide B (179) from over reduced butenolides using 1. 118 Scheme 52 Total synthesis of kadcoccinic acid A trimethyl ester (183) from advanced intermediate 181.…”

“…116 The Bobbitt's salt ( 1 ) modification to this procedures was used by Chen and co-workers in their racemic synthesis of ar-turmerone ( 173 ) (Scheme 50). 117 Oxidative rearrangement of tertiary allylic alcohol 172 to the corresponding enone proceeded rapidly to afford ar-turmerone ( 173 ) in 94% yield.…”

Water-soluble diphosphine ligands for rhodium-catalyzed branch-selective hydroaminomethylation of vinyl arenes with anilines in water

“…15 To the best of our knowledge, the only successful example was reported by Blum and co-workers, which employed a heterogeneous sol–gel immobilized rhodium catalyst at a Rh concentration of 6 mol%. 16 Based on the previous applications of diphosphine ligands derived from bis(2-(diphenylphosphaneyl)ethyl)amides in hydroformylation reactions, 17,18 we sought to develop the aqueous HAM protocols using similar ligands. This study reports the Rh-catalyzed branch-selective HAM of vinyl arenes with arylamines using the water-soluble ligands 19 under aqueous conditions.…”