Formal asymmetric enone aminohydroxylation: organocatalytic one-pot synthesis of 4,5-disubstituted oxazolidinones

Abstract

A formal asymmetric organocatalytic aminohydroxylation reaction of enones has been achieved via an aziridination-double S(N)2 sequence. As a part of the reaction design, the generated amino alcohol products are isolated as the corresponding oxazolidinones in good yields and excellent stereoselectivities.

Ring Expansions of Activated Aziridines and Azetidines

“…Trans-2,3-disubstituted N-Boc aziridines 280 were subjected to NaI-promoted cyclization in acetone at 60 C via aziridine ring opening at the α-carbonyl center followed by an intramolecular O-alkylation reaction to deliver the desired product 282 in good yields with excellent diastereoand enantioselectivity (Scheme 71) [128].…”

Enantiopure 4‐oxazolin‐2‐ones and 4‐methylene‐2‐oxazolidinones as chiral building blocks in a divergent asymmetric synthesis of heterocycles

“…The solvent was removed under vacuum. The residue was purified by column chromatography over silica gel (30 g/g of crude, hexane/EtOAc, 9:1) to afford a mixture of 1a (0.135 g, 55%) as an amber oil and 2a (16) [M + 1] + , 114 (22), 106 (100), 105 (38), 80 (32), 78 (18 2.2.3 | (4R,5R)-4-Hydroxy-4,5-dimethyl-3-((S)-1-phenylethyl)oxazolidin-2-one (12) and (4R,5S)-4-hydroxy-4,5-dimethyl-3-((S)-1phenylethyl)oxazolidinone (13) A mixture of 3a (0.880 g, 0.01 mol) and 4b (1.470 g, 0.01 mol) was placed in a threaded ACE glass pressure tube with a sealed Teflon screw cap under N 2 atmosphere. It was stirred and irradiated with MW (200 W) at 120°C for 90 minutes.…”

“…Likewise, the preparation of α‐amino alcohols and α‐amino acids has been designed based on the approach of the transformation of chiral 1,3‐oxazolidin‐2‐ones, which in turn can be obtained from optically pure α‐amino alcohols and α‐amino acids, among other substrates . The synthetic applicability of these heterocycles has increased with the development of new methods for their construction . Functionalized 4‐methylene‐1,3‐oxazolidin‐2‐ones have also proven to be versatile synthons in the formation of diverse molecular systems …”

“…[1][2][3][4][5][6][7][8][9] The synthetic applicability of these heterocycles has increased with the development of new methods for their construction. [14][15][16][17][18][19][20][21] Functionalized 4-methylene-1,3-oxazolidin-2-ones have also proven to be versatile synthons in the formation of diverse molecular systems. 22,23 Preformed or in situ-generated chiral enamines and enamides proved to be highly diastereoselective species in diversity-oriented asymmetric synthesis.…”

Asymmetric Organocatalytic Aziridination: Recent Advances

“…In 2012, the applicability of Cinchona alkaloid derived primary amine 65 was envisioned and validated even by Jørgensen et al., who selectively developed an enone‐aziridination‐iodide‐mediated double S N 2 reaction sequence forward the preparation of enantioenriched oxazolidinones 68 (Scheme ) …”