Direct conversion of epoxides to aziridines was achieved with guanidines as a nitrogen source. Stereochemical inversion at the chiral centers of epoxides was observed without loss of optical purity.
Synthesis of Oxazolidinones by using Carbon Dioxide as a C
<sub>1</sub>
Building Block and an Aluminium‐Based Catalyst
作者:Mani Sengoden、Michael North、Adrian C. Whitwood
DOI:10.1002/cssc.201901171
日期:2019.7.19
Oxazolidinone synthesis through the coupling of carbon dioxide and aziridines was catalysed by an aluminium(salphen) complex at 50–100 °C and 1–10 bar pressure under solvent‐free conditions. The process was applicable to a variety of substituted aziridines, giving products with high regioselectivity. It involved the use of a sustainable and reusable aluminium‐based catalyst, used carbon dioxide as a
efficiently promoted by ruthenium(VI) imidoporphyrin complexes and yields a mixture of 5‐aryl (A) and 4‐aryl (B) substituted oxazolidin‐2‐ones with a regioisomeric A/B ratio up to 99:1. Several oxazolidin‐2‐one molecules were synthesized at 100 °C and 0.6 MPa of carbondioxide by using the low catalytic loading of 1 mol‐%. The formation of a deactivated compound, deriving from the ruthenium catalyst, suggested
Three-component reaction of small-ring cyclic amines with arynes and acetonitrile
作者:David Stephens、Yu Zhang、Mathew Cormier、Gabriel Chavez、Hadi Arman、Oleg V. Larionov
DOI:10.1039/c3cc42854k
日期:——
A novel stereospecific three-component reaction of aziridines and azetidines with arynes and acetonitrile has been developed. The reaction affords N-aryl γ-aminobutyronitriles and δ-aminovaleronitriles that can be used as precursors and congeners of a number of bioactive compounds, such as pregabalin and lergotrile.
Stereoselective Isomerisation of N-Allyl Aziridines into Geometrically StableZ Enamines by Using Rhodium Hydride Catalysis
作者:Derek S. Tsang、Sharon Yang、France-Aimée Alphonse、Andrei K. Yudin
DOI:10.1002/chem.200701322
日期:2008.1.18
the most likely mechanism of isomerisation would involve a rhodium hydride addition/beta-hydride elimination sequence. We show that the observed selectivity cannot be adequately explained by this pathway and is more consistent with initial CH-activation followed by rearrangement to form a five-membered cyclometallated rhodium intermediate. This intermediate subsequently undergoes reductive elimination