Catalytic, Enantioselective Ring Opening of Aziridines

Abstract

Cooperative metal centers in a bimetallic catalyst facilitate the highly enantioselective ring opening of meso aziridines 1 with silyl nucleophiles (see scheme; TMS = trimethylsilyl). The 1,2-azidoamides 2 and 1,2-amidonitriles 3 obtained in this way in high yields and with up to 99% ee are valuable precursors to enantiomerically pure 1,2-diamines and beta-amino acids.

Highly Stereoselective Synthesis of New Aziridines via Baldwin Rearrangement and Their Potential Biological Activities

“…This is in accordance with well known Baldwin Rearrangement . Moreover, this transformation could lead to functionalized N‐ substituted aziridines, which are valuable intermediates in organic synthesis .…”

Synthesis of Some Novel Class of Bis(isoxazoline) and Bis(aziridine) Derivatives

“…As a part of our ongoing research programme to develop new methodologies in organic synthesis , herein, we report synthesis of some new bis(isoxazoline) derivatives (2) from terepthaldehyde in good to excellent yields under microwave irradiation (Scheme , Table ). Furthermore, these bis(isoxazoline) derivatives are found to have vast synthetic potential as they could be converted into synthetically more important new bis(aziridines) (3) . The newly reported bis(isoxazoline) derivatives are obtained as single pure compound when a mixture of bis(nitrone) 1 (1 equivalent) and alkynes (2 equivalents) is exposed to microwave irradiation for 5–10 min at 115 – 130°C.…”

Three‐Membered Heterocycles. Structure and Reactivity

“…Table 2.11) PhNH 2 Scheme 2.23 Ring opening of aziridines with aniline. The asymmetric ring-opening of meso aziridines such as 22b is a useful approach for accessing variously substituted chiral amines, and it has been the subject of some very good reviews [144,146,161]. One recently reported protocol involves the use of a titanium binolate catalyst, which can achieve ees of 99% [162].…”

“…Of course, sodium azide itself can be used as a reactant, with the addition being promoted efficiently by cerium trichloride heptahydrate [168], lithium perchlorate [169] or Oxone [170] (Scheme 2.25). Meso aziridines can be enantioselectively desymmetrized using a dimeric salen yttrium catalyst in near quantitative yield and excellent enantioselectivity [161].…”