An efficient method for the synthesis of acylals from aldehydes using silica-supported perchloric acid (HClO4–SiO2)
作者:Vinod T. Kamble、Vasant S. Jamode、Neeta S. Joshi、Ankush V. Biradar、Rameshchandra Y. Deshmukh
DOI:10.1016/j.tetlet.2006.05.125
日期:2006.7
The synthesis of acylals from structurally diverse aldehydes has been performed in excellent yields under solvent-free conditions using HClO4–SiO2 as a mild, convenient, reusable, and heterogeneous catalyst. The procedure is operationally simple, environmentally benign and has the advantage of enhanced atom utilization. Furthermore, the catalyst can be recovered simply and reused efficiently a number
HBF 4 -SiO 2 has been found to be an outstanding catalyst for the protection of carbonyl compounds as acylals under entirely solvent-free conditions. Some of the major advantages of this procedure are high yields, ease of operation, high chemoselectivity, high atom efficiency, and compatibility with other protecting groups.
Reinvestigation of the Mechanism ofgem-Diacylation: Chemoselective Conversion of Aldehydes to Variousgem-Diacylates and Their Cleavage under Acidic and Basic Conditions
作者:Veerababurao Kavala、Bhisma�K. Patel
DOI:10.1002/ejoc.200400584
日期:2005.1
aromatic aldehydes were obtained directly from the reaction of a variety of aliphatic and aromatic acid anhydrides in the presence of a catalytic quantity of tetrabutylammonium tribromide (TBATB) under solvent-free conditions. A significant electronic effect was observed during its formation as well as deprotection to the corresponding aldehyde. Chemoselective gem-diacylation of the aromatic aldehyde containing
Conversion of Aldehydes into Geminal Dicarboxylates (Acylals) Catalyzed by Lithium Tetrafluoroborate
作者:Norihiko Sumida、Kuniaki Nishioka、Tsuneo Sato
DOI:10.1055/s-2001-18774
日期:——
A variety of aldehydes react with acid anhydrides in the presence of a catalytic amount of lithium tetrafluoroborate to afford the corresponding geminal dicarboxylates (acylals) in good to excellent yields.
Catechol derivatives, and preventive and remedial preparations for regressive disorders in the central nervous system
申请人:MITSUI TOATSU CHEMICALS, Inc.
公开号:EP0261977A2
公开(公告)日:1988-03-30
Catechol derivatives which relate to the production of group. nerve growth factor in particular tissues of the brain are disclosed, as are methods for their synthesis, data on their physiological activity, and data on the toxicity of these derivatives. Examples of preparation for their administration are also disclosed.
The disclosed derivatives provide preventive and remedial effects for regressive disorders in the central nervous system including senile dementia of Alzheimer type: a preparation for this purpose includes a catechol derivative having the formula:
wherein R is two hydrogen atoms, two acyl groups, a -CO-group. -CO•CO- group, or -C(CH3)2- group, and wherein R1 and R2 are each independently a hydrogen atom or lower alkyl