Xonotlite Knoevenagel reaction

Xonotlite-t-butoxide has been used to catalyze the Knoevenagel condensation in which a carbonyl double bond (23) is converted to an olefinic bond (24) (reaction 6.22). The yields are generally 20-30% higher than with AI2O3 (Cabello et al., 1984 Texier-Boullet and Foucaud, 1982). 

Laszlo and coworkers found that xonotlite Ca6Si60i7(0H)2 doped with t-butoxide ions from KOC(CH3)3 is a superb basic catalyst.The material was a very efficient catalyst for a series of Michael reactions and Knoevenagel condensations. The results for Knoevenagel condensations are shown in Table 3.27. 

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