Catalytic Use of Indium(0) for Carbon−Carbon Bond Transformations in Water: General Catalytic Allylations of Ketones with Allylboronates
作者:Uwe Schneider、Masaharu Ueno、Shu̅ Kobayashi
DOI:10.1021/ja804182j
日期:2008.10.22
We have discovered the unprecedented catalytic use of In(0) for catalytic C-C bond transformations. Remarkably, these generalcatalytic allylations of ketones proceeded smoothly in water as a sole solvent under mild conditions, and water proved to be essential for these reactions. Both the displayed substrate scope and the functional group tolerance were excellent. Importantly, the In metal catalyst
我们发现了 In(0) 在催化 CC 键转换中前所未有的催化用途。值得注意的是,这些酮的一般催化烯丙基化反应在温和条件下在作为唯一溶剂的水中顺利进行,并且水被证明是这些反应必不可少的。显示的底物范围和官能团耐受性都非常好。重要的是,In 金属催化剂可以很容易地回收和重复使用,而不会损失催化活性。此外,当使用 α 取代的烯丙基硼酸酯时,观察到不寻常的结构选择性,仅提供正式的 α 加合物。此外,得到的叔均烯丙基醇具有极高的非对映选择性。
CpTiCl<sub>2</sub>
, an Improved Titanocene(III) Catalyst in Organic Synthesis
作者:Esther Roldan-Molina、Natalia M. Padial、Luis Lezama、J. Enrique Oltra
DOI:10.1002/ejoc.201801120
日期:2018.11.25
CpTiCl2, an improved titanocene(III) single‐electron transfer catalyst, under mild conditions provides excellent yields of homoallylic and homopropargylic alcohols in Barbier‐type allylation and propargylation reactions. Moreover, in the presence of a BOX ligand, it was capable of catalyzingenantioselective intramolecular allylations and propargylations (cyclizations) of ketones.
Practical and General Alcohol Deoxygenation Protocol
作者:Oliver P. Williams、Alyah F. Chmiel、Myriam Mikhael、Desiree M. Bates、Charles S. Yeung、Zachary K. Wickens
DOI:10.1002/anie.202300178
日期:——
A new protocol for alcoholdeoxygenation that functions across a wide range of alcohol structures is reported. This approach combines the reductive potency of carbon dioxide radical anion with acidic additives to promote the kinetically slow C(sp3)−O bond cleavage.