乙酰氧基膦酸酯是通过一步法获得的,该过程由乙酰膦酸二乙酯与前手性醛在包含手性路易斯酸,非手性路易斯碱和布朗斯台德碱的催化体系的存在下反应组成。使用三齿Schiff碱铝(III)Lewis酸性配合物,1 H -1,2,3-苯并三唑和叔胺(例如DBU )可获得最佳结果。在大多数情况下,以高收率获得目标化合物,但对映体比例适中(最高78:22)。
乙酰氧基膦酸酯是通过一步法获得的,该过程由乙酰膦酸二乙酯与前手性醛在包含手性路易斯酸,非手性路易斯碱和布朗斯台德碱的催化体系的存在下反应组成。使用三齿Schiff碱铝(III)Lewis酸性配合物,1 H -1,2,3-苯并三唑和叔胺(例如DBU )可获得最佳结果。在大多数情况下,以高收率获得目标化合物,但对映体比例适中(最高78:22)。
Iron-Doped Single-Walled Carbon Nanotubes as New Heterogeneous and Highly Efficient Catalyst for Acylation of Alcohols, Phenols, Carboxylic Acids and Amines under Solvent-Free Conditions
single-walled carbon nanotubes (Fe/SWCNTs) represent an efficient and new heterogeneous reusable catalyst for the acylation of a variety of alcohols, phenols, carboxylic acids and amines with acid chlorides or acid anhydrides undersolvent-freeconditions. The reactions of various primary, secondary, tertiary, and benzylic alcohols, diols, phenols, as well as aromatic and aliphatic amines give acylated
A high-yielding and convenient procedure for the efficient conversion of α-hydroxyphosphonates to α-acetyloxyphosphonates using acetic anhydride in the presence of catalytic amounts of copper triflate is described.
A convenient and eco-friendly procedure is described for the efficient preparation of a variety of α-acetyloxyphosphonates from their corresponding α-hydroxyphosphonates using acetic anhydride under microwave irradiation in the absence of solvent.
A new, efficient, and simple method for the one-pot synthesis of α-acetoxyphosphonates from aldehydes under solvent-free conditions
作者:Babak Kaboudin、Masoumeh Karimi
DOI:10.1016/j.bmcl.2006.07.083
日期:2006.10
efficient, and new method has been developed for the synthesis of alpha-acetoxyphosphonates from aldehydes through a one-pot reaction of aldehydes with diethylphosphite in the presence of acetic anhydride under solvent-free conditions using magnesium oxide. This method is easy, rapid, and high yielding for the one-potsynthesis of alpha-acetoxyphosphonates from aldehydes.
Nature of cationic intermediates derived from .alpha.-thiophosphoryl and .alpha.-thiocarbonyl mesylates. Neighboring thiophosphoryl and thiocarbonyl participation