Method and catalyst for synthesising aziridine

A method of synthesising aziridine (III), said method comprising contacting imine (I) or precursors thereof, with a diazo compound (II) in a solvent comprising a mixture of chloroform and dichloromethane, optionally wherein the chloroform and/or the dichloromethane is labelled with 2H or 3H, in the presence of a catalyst:

• wherein:
• R1 is a hydrogen atom;
• R2 is a substituted or unsubstituted aryl, alkylaryl, alkenylaryl or alkynylaryl group which optionally includes one or more heteroatoms in its carbon skeleton;
• R3 is a substituted or unsubstituted acyl, aryl, arylalkyl, or alkylaryl group which optionally includes one or more heteroatoms in its carbon skeleton;
• R4 is a hydrogen atom;
• R5 is a —CO—Rd, —CO—ORd, or —CO—N(Rd)2 group, wherein each —Rd is independently a hydrogen atom or a substituted or unsubstituted, straight-chain, branched or cyclic alkyl, alkenyl, alkynyl, acyl, aryl, arylalkyl, arylalkenyl, arylalkynyl, alkylaryl, alkenylaryl or alkynylaryl group which optionally includes one or more heteroatoms in its carbon skeleton;
• wherein the catalyst is a compound of formula (IV):
• wherein:
• X is O;
• R6 is —SO2—Re;
• Re is a substituted or unsubstituted, straight-chain, branched or cyclic alkyl, alkenyl, aryl, arylalkyl, arylalkenyl, alkylaryl, or alkenylaryl group which optionally includes one or more heteroatoms in its carbon skeleton;
• R7 and R8 together form a chiral bidentate ligand of formula (VIb), (VIb′) or (VIb″):
• wherein:
• Y6 and Y7 are each independently selected from a substituted or unsubstituted aryl or alkylaryl group which optionally includes one or more heteroatoms in its carbon skeleton;
• wherein the precursors of imine (I) comprise an amine H2NR3, and a carbonyl compound R1COR2;
• and
• wherein optionally the imine (I), one or more precursors thereof, and/or the diazo compound (II) are isotopically labelled such that the resultant aziridine (III) is also isotopically labelled.