García Jesús M, Odriozola José M, Razkin Jesús, Lapuerta Irati, Odriozola Amaiur, Urruzuno Iñaki, Vera Silvia, Oiarbide Mikel, Palomo Claudio
Departamento de Química Aplicada, Universidad Pública de Navarra, Campus de Arrosadía, 31006 Pamplona (Spain).
Chemistry. 2014 Nov 17;20(47):15543-54. doi: 10.1002/chem.201404452. Epub 2014 Oct 3.
An effective asymmetric route to functionalized 1,6- and 1,7-enynes has been developed based on a direct cross-aldol reaction between ω-unsaturated aldehydes and propargylic aldehydes (α,β-ynals) promoted by combined α,α-dialkylprolinol ether/Brønsted acid catalysis. This synergistic activation strategy is key to accessing the corresponding aldol adducts with high stereoselectivity, both enantio- and diastereoselectivity. The aldol reaction also proceeds well with propargylic ketones (α,β-ynones) thus enabling a stereocontrolled access to the corresponding tertiary alcohols. The utility of these adducts, which are difficult to prepare through standard methodology, is demonstrated by their transformation into trisubstituted bicyclic enones using standard Pauson-Khand conditions.
基于α,α-二烷基脯氨醇醚/布朗斯特酸联合催化促进的ω-不饱和醛与炔丙基醛（α,β-烯炔醛）之间的直接交叉羟醛反应，开发了一种有效的合成官能化1,6-和1,7-烯炔的不对称方法。这种协同活化策略是获得具有高立体选择性（对映选择性和非对映选择性）的相应羟醛加合物的关键。该羟醛反应与炔丙基酮（α,β-烯炔酮）也能顺利进行，从而能够立体控制地获得相应的叔醇。这些难以通过标准方法制备的加合物的实用性通过使用标准的鲍森-坎德条件将它们转化为三取代双环烯酮得到了证明。
