The trimethylgallium reagent was found to promote the addition of phenylacetylene to various aromatic and aliphatic aldehydes. This reaction was efficiently carried out in anhydrous CH2Cl2 at room temperature under mild conditions and the corresponding propargylic alcohols were obtained in good to excellent yields up to 98%.
Neighboring Carbonyl Group Assisted Hydration of Unsymmetrical Aryl Alkynes Overriding Regular Selectivity
作者:Kishor L. Mendhekar、Tapas R. Pradhan、N. Arjunreddy Mallampudi、Debendra K. Mohapatra
DOI:10.1002/ejoc.201900941
日期:2019.9.8
A mild and highly regioselective gold‐catalyzed hydration of γ‐acetoxy aryl alkynes leading to anti‐Markovnikov products by the assistance of a neighboringcarbonylgroup is presented.
Synthesis of Phosphonylated and Thiolated Indenones by Manganese(III)-Mediated Addition of Phosphorus- and Sulfur-Centered Radicals to 1,3-Diarylpropynones
Phosphorus- or sulfur-centered radicals generated from the reaction of manganese (III) acetate with dialkyl phosphonates or arylthiols undergo selective additions to conjugated alkynes followed by cyclization and rearomatization to afford 2-phosphonyl- or 2-thioaryl-substituted indenones in fair to good yields.
Organoborane-catalyzed selective 1,2-reduction of alkynones with hydride transfer: Synthesis of benzyl alkynes
作者:Lele Zhai、Zhigang Yang、Qinghong Man、Mingyu Yang、Yangqing Ren、Lei Wang、Huilin Li、Xuegong She
DOI:10.1016/j.tetlet.2022.153645
日期:2022.2
Benzyl alkynes are important organic building blocks in organic synthesis. We report herein a B(C6F5)3-catalyzed site-selective 1,2-reduction of readily available alkynones to access benzyl alkynederivatives. Under the developed conditions, an array of alkynone substrates are transformed into the corresponding benzyl alkyne products in good to excellent yields. This transformation displays many advantages
Enantioselective alkynylation of aromatic and heteroaromatic aldehydes catalyzed by resin-supported oxazolidine–titanium complexes
作者:Jincheng Mao、Zhijian Bao、Jun Guo、Shunjun Ji
DOI:10.1016/j.tet.2008.08.003
日期:2008.10
Highlyenantioselective asymmetric addition of terminal alkynes to various aromatic and heteroaromatic aldehydescatalyzed by the readilyavailable, low-cost, and reusable resin-supported oxazolidine 4 together with Ti(OiPr)4 provides the chiral propargylic alcohols with good to excellent yields (up to 98%) and enantioselectivities (up to 95%). The immobilized catalyst can be recovered and used for
易于获得,廉价且可重复使用的树脂负载的恶唑烷4与Ti(O i Pr)4一起催化,将末端炔烃高度对映体选择性地不对称地加成到各种芳族和杂芳族醛中,从而使手性炔丙醇具有良好的收率(优异的收率)(高达98%)和对映选择性(高达95%)。固定的催化剂可以回收并使用五个循环。