hydrogen-deuterium (H-D) exchange reaction on the benzylic site proceeded in D2O in the presence of a small amount of H2 gas. The use of the Pd/C-ethylenediamine complex [Pd/C(en)] as a catalyst instead of Pd/C led to the efficient deuterium incorporation into the benzylic site of O-benzyl protective groups without hydrogenolysis. These H-D exchange reactions provide a post synthetic and D(2)-gas-free deuterium-labeling
Regioselective Transfer Hydrodeuteration of Alkenes with a Hydrogen Deuteride Surrogate Using B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub> Catalysis
作者:Johannes C. L. Walker、Martin Oestreich
DOI:10.1021/acs.orglett.8b02718
日期:2018.10.19
4-dienes as surrogates for hydrogen deuteride (HD) gas is reported. The metal-free process proceeds under B(C6F5)3 catalysis presumably by deuteride abstraction to form borodeuteride [DB(C6F5)3]− and highly Brønsted-acidic Wheland intermediates. Low catalyst loadings (2.5 mol %) are used, and the reaction proceeds at room temperature.
据报道,使用单氘代环己-1,4-二烯作为氘代氢(HD)气体的替代物,对烯烃进行区域选择性加氢氘代。无金属过程可能在B(C 6 F 5)3催化下进行,可能是通过氘代抽提而形成的硼氢化氘[DB(C 6 F 5)3 ] -和高度布朗斯台德酸性Wheland中间体。使用低催化剂负载量(2.5mol%),并且反应在室温下进行。
Rhodium‐Catalyzed Stereoselective Deuteration of Benzylic C–H Bonds via Reversible η
<sup>6</sup>
‐Coordination
作者:Qi‐Kai Kang、Yuntong Li、Kai Chen、Hui Zhu、Wen‐Qiang Wu、Yunzhi Lin、Hang Shi
DOI:10.1002/anie.202117381
日期:2022.3.7
A novel rhodium-catalyzed H/D exchange of primary, secondary, and tertiary benzylic C−H bonds by means of an η6-coordination strategy is reported. The method, which features high regioselectivity and stereoretention, shows broad functional group tolerance and has been used in late-stage labeling of pharmaceuticals.
报道了通过 η 6配位策略实现伯、仲和叔苄基 C-H 键的新型铑催化 H/D 交换。该方法具有高区域选择性和立体保留性,具有广泛的官能团耐受性,已用于药物的后期标记。
Indium Tribromide‐Catalysed Transfer‐Hydrogenation: Expanding the Scope of the Hydrogenation and of the Regiodivergent DH or HD Addition to Alkenes
作者:Luomo Li、Gerhard Hilt
DOI:10.1002/chem.202101259
日期:2021.8.2
The transfer-hydrogenation as well as the regioselective and regiodivergentaddition of H−D from regiospecific deuterated dihydroaromatic compounds to a variety of 1,1-di- and trisubstituted alkenes was realised with InBr3 in dichloro(m)ethane. In comparison with the previously reported BF3⋅Et2O-catalysed process, electron-deficient aryl-substituents can be applied reliably and thereby several restrictions
使用 InBr 3在二氯(甲烷)中实现转移氢化以及从区域特异性氘代二氢芳族化合物到各种 1,1-二和三取代烯烃的 HD 的区域选择性和区域发散加成。与之前报道的 BF 3 ⋅Et 2 O 催化工艺相比,缺电子芳基取代基可以可靠地应用,从而可以取消一些限制,并且可以在加氢氘化和氘化氢化转移中成功转化新型底物-氢化反应。
Nickel-Catalyzed Reductive Deoxygenation of Diverse C–O Bond-Bearing Functional Groups
作者:Adam Cook、Haydn MacLean、Piers St. Onge、Stephen G. Newman
DOI:10.1021/acscatal.1c03980
日期:2021.11.5
We report a catalytic method for the direct deoxygenation of various C–O bond-containing functional groups. Using a Ni(II) pre-catalyst and silane reducing agent, alcohols, epoxides, and ethers are reduced to the corresponding alkane. Unsaturated species including aldehydes and ketones are also deoxygenated via initial formation of an intermediate silylated alcohol. The reaction is chemoselective for