The first example of Cu(ii)-mediated oxidative coupling of aromatic carboxylic acids with the C(sp3)–H bond adjacent to the keto group ofN,N-dialkylamides has been developed.
The invention relates to compounds of formula
wherein the substituents are as described in claim
1
. Compounds of formula I are modulators for amyloid beta and thus, they may be useful for the treatment or prevention of a disease associated with the deposition of β-amyloid in the brain, in particular Alzheimer's disease, and other diseases such as cerebral amyloid angiopathy, hereditary cerebral hemorrhage with amyloidosis, Dutch-type (HCHWA-D), multi-infarct dementia, dementia pugilistica and Down syndrome.
Aldol condensation of amides using phosphazene-based catalysis
作者:Siong Wan Foo、Shun Oishi、Susumu Saito
DOI:10.1016/j.tetlet.2012.07.129
日期:2012.10
new method for the direct aldolcondensation of unactivated amides using 1,3,5-triazo-2,4,6-triphosphorine-2,2,4,4,6,6-hexachloride (TAPC)-based phosphorous/SO42− catalysis. The SO42− species in a reaction mixture enhances the reaction rate of the catalysis. In principle, no metal sources are required for the generation of the catalyst, and there is no requirement for the use of stoichiometric quantities
我们已经开发出一种新的方法,用于使用1,3,5-三唑-2,4,6-三磷-2,2,4,4,6,6-六氯化物(TAPC)的磷直接将未活化的酰胺进行羟醛缩合/ SO 4 2-催化。反应混合物中的SO 4 2-物种提高了催化反应的速率。原则上,不需要金属源来生成催化剂,也不需要使用化学计量的酸或碱。该催化剂体系在相对酸性的条件下可操作。在酸性条件下进行反应的一个主要优点是醛和缩醛都能够通过脱水在酰胺羰基的α-碳上形成碳-碳键。
Condensation of aromatic aldehydes with N,N-dimethylacetamide in presence of dialkyl carbonates as dehydrating agents
AbstractReactions of benzaldehydes with excess N,N-dimethylacetamide at 140 °C in the presence of diethyl carbonate as dehydrating agent and a base gave (E)-N,N-dimethylcinnamamides in good yields. If hydroxybenzaldehydes are used as substrates the reaction is accompanied by alkylation. Graphical abstract