4,4′-Di-tert-butylbiphenyl-catalysed reductive opening of azetidines with lithium: A direct preparation of 3,N-dilithioalkylamines

✍ Scribed by Juan Almena; Francisco Foubelo; Miguel Yus

• Book ID: 104203425
• Publisher: Elsevier Science
• Year: 1994
• Tongue: French
• Weight: 665 KB
• Volume: 50
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(01)85645-3

✦ Synopsis

The reaction of N-phenylazetidine la with an excess of lithium powder aud a catalytic amount of 4#-ditert-butylbiphenyl (5 mol 56) in THF at -15°C leads to~rrespondiag diauion 2a, which by treatment with different electrophiles (H$I, Dfl, BuKJHO, PhCHO. (CH&CO. PhCH=NPh. CO2) yields, aftez hydrolysis with water, the expected functionalysed amines Jaa-ah. The same method applied to N-isopropyl-Z-phenylaztidine 1 c affords compounds 3c.a.ee (electrophiles: H20. D20, PhCHO, Me&O, CH&HCH2Br) resulting from the more stable benzylic intermediate 2e. Finally, the regiochemistry in the reductive opening of 2-methyl-N-phenylazetidine Id followed by deut~lysis was studi& a mixture of both regioisomers Ma+3da' was obtained, the ratio being the opc&e as expected according to the stability of both intermediatea 2d aud 2d'.