Solid-Phase synthesis of cyclic Sulfonamides and Sulfamides employing a Ring-Closing Metathesis Cleavage strategy

Abstract

A series of novel 7-membered cyclic sulfonamides and sulfamides were prepared in good to excellent yields using a ring-closing metathesis (RCM) approach. Model studies in solution indicated the sulfonamides were suitable substrates for RCM and they were thus employed on
the solid-phase. A strategy that involved simultaneous cyclisation and cleavage from the resin was developed and applied to the synthesis of cyclic sulfonamides. The solid supports used included commercially available Merrifield resin and a carboxyethyl resin derived from the former. The effect of three different linkers upon the efficiency of the reaction was investigated: a relatively inflexible allylic linker, a flexible linker and a novel double armed linker. Whereas the RCM cleavage strategy failed when using the inflexible linker, cyclisative release from the more flexible single and double armed linkers proceeded efficiently using 5 mol% of catalyst. In fact, the double armed linker was successfully employed even with 1 mol% of catalyst. Following a similar strategy, the synthesis of 7 membered cyclic sulfamides met with success in the solution-phase but preliminary efforts to transfer it to the solid-phase failed in part due to lack of time. Methods for hydroxylation of the double bond on the sulfamides were developed leading to potential HIV protease inhibitors.

More information

Identifiers

Catalogue record

Export record