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An investigation of Knoevenagel condensation reaction in microreactors using a new zeolite catalyst

“…d The amount of organic moieties on the zeolites was determined from the TGA/DTA data. It was suggested that the loss of surface area was caused by breakage of Si-O-Si bonds leading to pore collapse [8], but it was also possible that the smaller surface area was due to the restricted access to the zeolite pore channel caused by the presence of large cesium counterions [25]. The amount of grafted organic amino groups was found by thermal gravimetric and differential thermal analyses (TGA/DTA, Setaram) to be 1.4 and 1.2 m moles/g for NaX-NH 2 and CsNaX-NH 2 , respectively.…”

“…NaOH and KOH), pyridine and piperidine are the traditional catalysts used in these reactions. However, basic zeolites such as Cs-exchanged NaX (CsNaX) and GeX, as well as cesium and cesium-lanthanum impregnated mesoporous MCM-41 are also able to catalyze the Knoevenagel condensation under mild reaction conditions [6][7][8][9]. It has been shown that nitridation of zeolite materials with ammonia produces more basic catalysts than the ion-exchanged zeolites [10].…”

Zeolite Effects on Catalytic Transformations of Fine Chemicals

“…At contrast Cs 2 0-MCM-41 can also be used for the addition of C0 2 to epoxides, or for Michael addition of one or two molecules of diethyl malonate on neopentylglycol diacrylate (37,38) : …”

A mild, efficient and green route for acylation of alcohols and phenols with acetic anhydride and Na-Y zeolite

“…The H-Y zeolite [4], MCM-41 [5] and other porous materials have been already used as catalyst for protection of alcohols and phenols as their ethers. Zeolite H-beta has been used as a catalyst in organic chemical conversions such as alkylation [6], ketal-acetal formation etc.…”