炔丙醇和胺是有机合成中的通用组成部分。我们展示了一种简单的酶级联反应,可以从容易获得的外消旋起始材料合成对映异构纯的炔丙醇和胺。在第一步中,来自Agrocybe aegerita的过氧化酶将外消旋炔丙醇转化为相应的酮,然后使用来自开菲尔乳杆菌的 ( R )-选择性醇脱氢酶或 ( S )-选择性醇脱氢酶将其转化为对映体纯醇来自布罗基热厌氧菌. 此外,使用来自土曲霉的( R )-选择性胺转氨酶或来自紫色色杆菌的( S )-选择性胺转氨酶,建立了将外消旋醇酶促Mitsunobu型转化为对映体富集的炔丙基胺。一锅两步级联反应以 70-99% 的产率产生了范围广泛的对映体富集的醇和胺产物。
Ni<sup>I</sup>Catalyzes the Regioselective Cross-Coupling of Alkylzinc Halides and Propargyl Bromides to Allenes
作者:Rita Soler-Yanes、Iván Arribas-Álvarez、Manuel Guisán-Ceinos、Elena Buñuel、Diego J. Cárdenas
DOI:10.1002/chem.201603758
日期:2017.1.31
We describe the unprecedented formation of allenes by Ni‐catalyzed cross‐coupling of propargyl bromides with alkylzinc halides. The reaction regioselectivity is complementary to the previously reported formation of propargyl‐coupled compounds. Experiments support the formation of NiI complexes as the active species and the participation of radical intermediates. Kinetic studies showed that the reaction
Synthesis of Alkylidene(<i>gem</i>-Difluorocyclopropanes) from Propargyl Glycolates by a One-Pot Difluorocyclopropenation/Ireland–Claisen Rearrangement Sequence
difluorocyclopropenation/Ireland–Claisenrearrangement sequence applied to readily available propargyl glycolates was developed as a route toward functionalized alkylidene(gem-difluorocyclopropanes). This strategy conveniently avoids the isolation of the unstable 3,3-difluorocyclopropenylcarbinyl glycolates arising from the difluorocyclopropenation. The Ireland–Claisenrearrangement proceeds with high
CH-Diazomethane Sulfonamides Generated in Situ for Intramolecular [3+2] Cycloaddition of Alkynes: An Entry into Novel Pyrazole-Fused Five-Membered Sultams
sulfonamides carrying various propargylic groups are generated in situ from their acetyl precursors. Without purification, these compounds undergo a slow, albeit clean and efficient, intramolecular [3+2] cycloaddition to give pyrazole-fused five-membered sultams. The latter are the first analogues of medicinally important (hetero)arene-fused five-membered sultams containing a five-membered nitrogenous
Gold Meets Rhodium: Tandem One-Pot Synthesis of β-Disubstituted Ketones via Meyer–Schuster Rearrangement and Asymmetric 1,4-Addition
作者:Max M. Hansmann、A. Stephen K. Hashmi、Mark Lautens
DOI:10.1021/ol4011739
日期:2013.7.5
An asymmetric one-pot tandem Au/Rh-catalyzed synthesis of highly enantioenriched β-disubstituted ketones starting from racemic propargyl alcohols is disclosed. The compatibility of the two metal complexes (Au/Rh) and their orthogonal ligand systems (NHC/diene) in this bimetallic catalytic system is investigated.
Lewis-base-catalysed selective reductions of ynones with a mild hydride donor
作者:F. Schömberg、Y. Zi、I. Vilotijevic
DOI:10.1039/c8cc00058a
日期:——
Ynones are efficiently reduced with a mild hydride donor in the presence of a catalytic amount of nucleophilic phosphines. The reactions are selective 1,2-reductions that give propargyl alcohols in yields of up to 96%. It is proposed that success in these reactions depends on the activation of ynones by a Lewis base catalyst. A protic additive plays a key role in suppressing the undesired reaction