N-alkoxycarbonylamino sulfones

In this chapter, we wish to disclose our results on the nucleophilic addition of carbon nucleophiles to N-alkoxycarbonylamino sulfones. Both allyltrimethylsilane and silyl enolates will be considered as nucleophiles. The corresponding amines were obtained efficiently in the presence of 0.5-5 mol% of Bi(0Tf)34H20 [57,58]. 

Table 4 Bi(0Tf)3-4H20-catalyzed Mannich-type reactions involving N-alkoxycarbonylamino sulfones and trimethyl(l-phenylvinyloxy)silane...

Bismuth triflate was found to be an efficient catalyst in the Mannich-type reaction of silyl enolates with N-alkoxycarbonylamino sulfones. The reaction proceeded smoothly with a low catalyst loading of bismuth triflate (0.5-1.0 mol%) to afford the corresponding protected -aminocarbonyl compounds in very good yield (Equation 7) [29]. 

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