4-(4,6-Dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium Chloride

Introduction

4-(4,6-Dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholi­nium chloride (DMTMM) is a highly effective coupling reagent used for both amide synthesis and for the preparation of esters.[1] [2] The advantages of using DMTMM as a coupling reagent include excellent product yields and the possibility that reactions can be performed in one step at room temperature and under atmospheric conditions.[ ¹ ] Readily removed and solubilising solvents (e.g. MeOH, EtOH, i-PrOH) including water, can be used in reactions with DMTMM and no drying requirements are needed for the reaction solvents.[ ³ ] Furthermore, no additives are required and acids can be activated in situ.[ ² ]

The by-product of the reaction with DMTMM (2-hydroxy-4,6-dimethoxy-1,3,5-triazine, HO-MDT) is highly water soluble and can be easily removed from the main reaction product.[2] [4] The recovered by-product can also be converted back into the starting material via 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT).

DMTMM is commercially available, but can also be prepared in a straightforward manner by reaction between CDMT and n-methylmorpholine (NMM) or from cyanuric chloride.[3] [5] The reagents for the preparation of ­DMTMM are inexpensive, providing an economical benefit when using this reagent.

Scheme 1 Preparation of DMTMM from CDMT

• References

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