Enantioselective Nitrene Transfer to Sulfides Catalyzed by a Chiral Iron Complex

Abstract

Eisenarbeiten: Der enantioselektive Transfer eines Nitrens auf ein Sulfid gelingt mit einem chiralen Eisen(III)/PyBOX‐Katalysator (siehe Schema). Verschiedene Sulfimide wurden so mit hohen Enantioselektivitäten und Ausbeuten erhalten. Die Anwendung dieses Protokolls auf die Synthesen enantiomerenangereicherter Sulfoximine und eines Epoxids wurde ebenfalls gezeigt.

Rhodium‐Catalyzed Stereoselective Amination of Thioethers with N‐Mesyloxycarbamates: DMAP and Bis(DMAP)CH2Cl2 as Key Additives

“…Nitrogen heterocycles, such as pyridines, were also compatible with the reaction conditions (entry 11). [12,20] Cleavage of the carbamate was achieved using Zn in AcOH to produce free sulfoximine 18 in 94 % yield as a single enantiomer. Herein we demonstrate that 14, which contains bulky isopropyl groups, was produced in 76 % yield and a good d.r.…”

“…[5e, 6] Although metalcatalyzed diastereoselective reactions with chiral substrates [7] or chiral reagents [8] have been delineated, they often have limited substrate scope. [12] Although high yields and selectivities are typically observed in the synthesis of aromatic sulfilimines, only modest yields and selectivities are reported with hindered and aliphatic substrates. [12] Although high yields and selectivities are typically observed in the synthesis of aromatic sulfilimines, only modest yields and selectivities are reported with hindered and aliphatic substrates.…”

“…The recent discovery of sulfilimine cross-links in collagen IV networks has illustrated the importance of this class of compounds, thus highlighting the need for the development of methods to generate this moiety. [12] Although high yields and selectivities are typically observed in the synthesis of aromatic sulfilimines, only modest yields and selectivities are reported with hindered and aliphatic substrates. [1a, 5] A number of transition-metal complexes have been reported to catalyze the amination of thioethers, presumably via the formation of metal-nitrene species.…”

“…[1a, 5] A number of transition-metal complexes have been reported to catalyze the amination of thioethers, presumably via the formation of metal-nitrene species. [12] Although high yields and selectivities are typically observed in the synthesis of aromatic sulfilimines, only modest yields and selectivities are reported with hindered and aliphatic substrates. The catalytic enantioselective ami-nation of thioethers with iminoiodinanes has been developed using chiral Cu, [9] Mn, [10] Ru, [11] and Fe complexes.…”

Asymmetric Enzymatic Synthesis of Allylic Amines: A Sigmatropic Rearrangement Strategy

“…14 This strategy would establish a biocatalytic route to chiral allylic amines, compounds that are biologically active 15 as well as valuable synthetic intermediates. 16,17 Furthermore, expanding the breadth of enzymatic amination reactions will facilitate the construction of non-natural in vivo pathways for chiral amine production.…”