STUDIES ON PHOSPHONIUM YLIDS. XI. ON THE REACTION OF WITTIG REAGENTS WITH p-BENZO QUINONEDIMETHANE-SULFONIMINES. A NEW 1,2-ADDITION REACTION ON p-QUINONEIMINES

Abstract

The reaction of carbmethoxymethylene (1a)-, carbethoxymethylene (1b)-, acetylmethylene (1c)-, and benzoylmethylene (1d)-triphenylphosphoranes with N,N′-2,5-cyclohexadiene-1,4-diylidenebis (methanesulfonamide) (IIa) and its 2-chloro-derivatives IIb afforded the new ylid-phosphoranes IIIa-g via 1,2-addition reaction. Structural reasoning for compounds 111 was based on compatible analytical and spectral data (IR, ¹H NMR, ³¹P NMR, ¹³C NMR, and MS). The mechanism that accounts for formation of adducts III is discussed.

Key Words:

• Wittig reagents (1)
• N,N′-2,5-cyclohexadiene-1,4-diylidene-bis(methanesulfonamide) (IIa)
• N, N′-(2-chloro-2,5-cyclohexadiene-1,4-diylidene)bis(methanesulfonamide) (IIb)
• alkyl 1-[(methylsulfonyl)amino]-4-[(methylsulfonyl)imino]-α-(triphenylphosphoranylidene)-2,5-cyclohexadiene-1-acetate (IIIa,b)
• N-[4-[(methylsulfonyl)amino]-4-[2-oxo-1- triphenvlphosphoranvlidene)-propyl]-2,5-cyclohexadien-1-ylidene] methanesulfonamide (IIIc)
• N-[4-[(meihylsulfonyl)amino]-4-[2-oxo-2-phenyl-1-(triphenylphosphoranylidene)ethyl]-2,5-cyclohexadien-1-ylidene] methanesulfonamide (IIId)