Efficient and selective nitrile hydration reactions in water catalyzed by an unexpected dimethylsulfinyl anion generated in situ from CsOH and DMSO

Abstract

Dimethylsulfinyl anions derived from CsOH–DMSO catalyzed nitrile hydration reactions in water to give the versatile amides via interesting DMSO-participating mechanisms.

Immediate hydroxylation of arenes to phenols via V-containing all-silica ZSM-22 zeolite triggered non-radical mechanism

“…Such observation reveals that in the first step of Fig. 1a , the V(V) species of (VO 3 ) n n − in VSZ-5 were transformed into V(IV), whilst CH 3 CONH 2 was created from CH 3 CN 51 . No CH 3 CONH 2 was detectable in the absence of VSZ-5 or by using other acids/solvents, implying that this transformation only happened in the simultaneous presence of VSZ-5/CH 3 CN/H 2 SO 4 .…”

Selective Hydration of Nitriles to Corresponding Amides in Air with Rh(I)-N-Heterocyclic Complex Catalysts

“…Transition metal-free processes have been described, too, such as the CsOH/DMSO superbase system [30], NaOH as catalyst [31], or tBuOK under anhydrous conditions [32]. Nitrile hydratases catalyze the hydration of nitriles to the corresponding amides under softer conditions and have been successfully used, for example, for production of levetiracetam (Keppra ® ) for the treatment of epilepsy [3].…”

DMSO‐Triggered Complete Oxygen Transfer Leading to Accelerated Aqueous Hydrolysis of Organohalides under Mild Conditions

“…We have previously reported that dimethylsulfinyl anion generated from DMSO and CsOH could add to nitriles to furnish a CsOH/DMSO‐catalyzed mild, efficient, and controllable nitrile hydration reaction involving a DMSO‐facilitated oxygen transfer mechanism (Scheme A) . Because, as reported previously, DMSO is also a good O‐nucleophile and alkoxysulfonium salts ROS + R 1 R 2 ⋅ X − generated in different ways could react with nucleophiles to afford substitution products (Scheme b), we hypothesized that DMSO may also react with electrophilic organohalides to give ROS + Me 2 ⋅ X − intermediates and further react with H 2 O or OH − , consequently facilitating the hydrolysis reaction (Scheme c).…”

“…Although DMSO has been reported as a dipolar aprotic solvent to promote organohalide hydrolysis reaction in metal‐mediated, photocatalytic, and metal‐free reactions, knowledge of how DMSO facilitated these reactions was limited to the understanding as a dipolar solvent to enhance water's nucleophilicity. Based on our previous findings in nitrile hydration reaction and those in screening the conditions (Table , entry 8), we propose the reaction mechanism given in Scheme c.…”

“…To probe the reaction mechanism, 18 O‐labeled DMSO was prepared according to a reported procedure and used it in the reaction with 1 a . When 1 a was heated with 18 O‐DMSO (94 % 18 O) at 50 °C, 93 % 18 O‐enriched PhCH 2 OH ( 2 a ) could be obtained as determined by high‐resolution mass spectrometry [Eq. ]…”