Chemoselective Deprotection of Sulfonamides Under Acidic Conditions: Scope, Sulfonyl Group Migration, and Synthetic Applications

Javorskis, Tomas; Orentas, Edvinas

doi:10.1021/acs.joc.7b02507

Cited by 56 publications

(64 citation statements)

References 116 publications

(81 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Very recently, it was described that chemoselective acidic hydrolysis of sulfonamides can be effected with trifluoromethanesulfonic acid (triflic acid) in a wide variety of examples of practical importance. [22] Those conditions, that involve the treatment of the sulfonamide with 2 equiv. of triflic acid in dichloroethane at room temperature for 12 h, were applied to substrate 5 c, affording the deprotected quinolone 6 in 71% yield (Scheme 3).…”

Section: Resultsmentioning

confidence: 99%

“…Finally, the deprotection of the sulfonamide moiety was attempted. Very recently, it was described that chemoselective acidic hydrolysis of sulfonamides can be effected with trifluoromethanesulfonic acid (triflic acid) in a wide variety of examples of practical importance . Those conditions, that involve the treatment of the sulfonamide with 2 equiv.…”

Section: Resultsmentioning

confidence: 99%

“…[22] Those conditions, that involve the treatment of the sulfonamide with 2 equiv. Very recently, it was described that chemoselective acidic hydrolysis of sulfonamides can be effected with trifluoromethanesulfonic acid (triflic acid) in a wide variety of examples of practical importance.…”

Section: Full Papermentioning

confidence: 99%

See 2 more Smart Citations

Domino Synthesis of 3‐Alkyliden‐2,3‐Dihydro‐4‐Quinolones

et al. 2019

View full text Add to dashboard Cite

The synthesis of 3-alkyliden-2,3-dihydro-4-quinolones has been accomplished in a domino fashion through a three-step sequence that comprised an initial aza-Baylis-Hillman reaction, followed by a 1,3rearrangement and an intramolecular amination. Starting from readily available aryl vinyl ketones and Ntosyl imines, the reaction with PPh 3 , CsOAc and CuI in CH 3 CN gave rise, in good overall yields, to final 3alkyliden-4-quinolone derivatives, valuable scaffolds in medicinal chemistry. The simultaneous addition of two bases, PPh 3 and CsOAc, was found to be crucial for the success of the process. While PPh 3 promoted the reversible aza-Baylis-Hillman reaction, CsOAc triggered the subsequent 1,3-rearrangement, which shifted the initial equilibrium and allowed to complete the synthetic sequence upon the addition of CuI.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Domino Synthesis of 3‐Alkyliden‐2,3‐Dihydro‐4‐Quinolones

et al. 2019

View full text Add to dashboard Cite

show abstract

“…1 H NMR (400 MHz, CDCl 3 ) δ 6.99 (d, J = 8.5 Hz, 2H), 6.54 (d, J = 8.4 Hz, 2H), 3.51 (s br, 1H), 2.80 (s, 3H), 2.24 (s, 3H). 13 (13), 91 (41), 89 (10), 79 (12), 78 (15), 77 (26), 65 (25), 63 (16), 60 (12), 53 (11), 52 (18), 51 (26), 50 (16).…”

Section: Methylation Of Synthesized Sulfonamides (Methods F)mentioning

confidence: 99%

“…A light yellow solid was isolated in 71% yield (0.71 mmol, 207 mg). 1 (10), 116 (100), 111 (27), 90 (11), 89 (61), 75 (35), 63 (37), 51 (10), 50 (17). HRMS (ESI) m/z: [M + H] + calcd for C 14 H 11 ClNO 2 S 292.0194; found 292.0189.…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

Transition-Metal-Free and Visible-Light-Mediated Desulfonylation and Dehalogenation Reactions: Hantzsch Ester Anion as Electron and Hydrogen Atom Donor

et al. 2020

View full text Add to dashboard Cite

Novel approaches for N-and O-desulfonylation under room temperature (rt) and transition-metal-free conditions have been developed. The first methodology involves the transformation of a variety of N-sulfonyl heterocycles and phenyl benzenesulfonates to the corresponding desulfonylated products in good to excellent yields using only KO t Bu in dimethyl sulfoxide (DMSO) at rt. Alternately, a visible light method has been used for deprotection of N-methyl-N-arylsulfonamides with Hantzsch ester (HE) anion serving as the visible-light-absorbing reagent and electron and hydrogen atom donor to promote the desulfonylation reaction. The HE anion can be easily prepared in situ by reaction of the corresponding HE with KO t Bu in DMSO at rt. Both protocols were further explored in terms of synthetic scope as well as mechanistic aspects to rationalize key features of desulfonylation processes. Furthermore, the HE anion induces reductive dehalogenation reaction of aryl halides under visible light irradiation.

show abstract

Triflic acid‐Mediated Expedient Synthesis of Benzo[a]fluorenes and Fluorescent Benzo[a]fluorenones

Mandal

Balamurugan

2018

Adv Synth Catal

View full text Add to dashboard Cite

Fluorene‐based polyaromatic hydrocarbons are renowned compounds for materials applications. Herein, a straightforward route via in situ acetal formation has been presented to access benzo[a]fluorenes by a triflic acid promoted cationic cycloisomerization of enynones in presence of trimethyl orthoformate under metal‐free conditions. In the absence of trimethyl orthoformate, the same reaction results in benzo[a]fluorenones. All the synthesized benzo[a]fluorenones are highly fluorescent in solution phase with high Stokes shift while the corresponding benzo[a]fluorenes are not fluorescent.magnified image

show abstract

Chemoselective Deprotection of Sulfonamides Under Acidic Conditions: Scope, Sulfonyl Group Migration, and Synthetic Applications

Cited by 56 publications

References 116 publications

Domino Synthesis of 3‐Alkyliden‐2,3‐Dihydro‐4‐Quinolones

Domino Synthesis of 3‐Alkyliden‐2,3‐Dihydro‐4‐Quinolones

Transition-Metal-Free and Visible-Light-Mediated Desulfonylation and Dehalogenation Reactions: Hantzsch Ester Anion as Electron and Hydrogen Atom Donor

Triflic acid‐Mediated Expedient Synthesis of Benzo[a]fluorenes and Fluorescent Benzo[a]fluorenones

Contact Info

Product

Resources

About