Full N,N-Methylation of 4,4′-Methylenedianiline with Dimethyl Carbonate: A Feasible Access to 4,4′-Methylene bis(N,N-Dimethylaniline)

Table 1

Formation of MBDMA over various catalysts.

Catalysts	MDA	MBDMA
	Conversion; /%	Selectivity; /%	Yield; /%
None	61.2	None	None
Hβ	61.8	None	None
ZSM-5	62.2	None	None
NaX	100	28.7	28.7
NaY	100	91.1	91.1
MCM-41	86.4	None	None

Reaction Conditions. DMC 27.0 g (0.30 mol), MDA 1.98 g (0.01 mol), catalyst 1.98 g, reaction time 6 h, and reaction temperature 180°C.