Reductive Detriflylation of N-Triflylamides with Red-Al

Abstract

Reduction of cis-N-triflylaziridines with 10 equiv of Red-Al in toluene at -40 to 0 °C selectively afforded corresponding deprotected parent aziridines in good to high yields. N,N-Dialkyltriflylamides were also successfully cleaved under similar reaction conditions.

Trifluoromethanesulfonamides and Related Compounds

“…196 The N-triflylaziridines can be further deprotected by reductive detriflylation with sodium bis(2-methoxyethoxy)aluminum dihydride (Red-Al). 197 As a triflamidating agent, triflylimino-λ 3 -bromane reacts also with pyridines and related N-heterocycles to give Niminoammonium ylides. 198 Noteworthy is that only triflamide gives the above sulfonylimino-λ 3 -bromane; arenesulfonamides react with the same difluoro-λ 3 -bromane in a different manner, giving rise to the Hofmann rearrangement products ArNH-SO 2 F. 199…”

“…A modification of this procedure is preparation of the diacetoxy derivative from the above difluoro-λ 3 -bromane, which is an analogue of the well-known diacetoxy-λ 3 -iodane, PhI(OAc) 2 , and its further reaction with alkenes and triflamide . The N -triflylaziridines can be further deprotected by reductive detriflylation with sodium bis(2-methoxyethoxy)aluminum dihydride (Red-Al) …”

Synthesis of Optically Pure 3,3′-Diaryl Binaphthyl Disulfonic Acids via Stepwise N–S Bond Cleavage

“…Moreover, a significant amount of naphthalene was obtained due to overreaction with reactive LiAlH 4 . In place of LiAlH 4 , when we used less reactive NaAlH 2 (OC 2 H 4 OCH 3 ) 2 (Red-Al, 10 equiv), 14 was obtained in 71% yield (entry 3). In entry 3, more than three spots were observed in TLC analysis after the reduction step.…”

Visible‐Light‐Assisted Synthesis of Allylic Triflamides via Dual Acridinium/Co Catalysis

“…The marked Brønsted acidity of the “NHTf” motif (pKa ca. 6.3, for TfNH 2 ), [3a–c] the ready access to unprotected amino groups [3d–f] and the chemical flexibility of the allyl unit [2a,c] account for the prominent role played by this class of nitrogen‐based compounds in the organic chemistry scenario.…”