17861-18-6Relevant articles and documents
Room-Temperature meta-Functionalization: Pd(II)-Catalyzed Synthesis of 1,3,5-Trialkenyl Arene and meta-Hydroxylated Olefin
Bera, Milan,Sahoo, Santosh K.,Maiti, Debabrata
, p. 3575 - 3579 (2016)
Development of meta-C-H functionalization reactions at room temperature continues to be a tough challenge. Use of a phosphonate linkage allowed a Pd (II)-catalyzed meta-C-H functionalization at room temperature while incorporating a cyanophenol-based dire
Xanthate-mediated synthesis of (E)-alkenes by semi-hydrogenation of alkynes using water as the hydrogen donor
Luo, Xianglin,Chen, Xiuwen,Chen, Lu,Zhang, Kun,Li, Yibiao
supporting information, p. 2170 - 2173 (2019/02/24)
Semi-hydrogenation of alkynes is one of the most widely used methods for obtaining alkenes in laboratory preparation and in industry. Transition metal catalysts have been extensively studied for this transformation, but the tolerance of functional groups, such as pyridine,-OH,-NH2,-Bpin, and halides, and the toxicity of the trace amount of transition metal catalysts are still highly challenging. In this study, we report a general and robust strategy to achieve the semi-hydrogenation of alkynes using inexpensive and commercially available xanthate as the mediator. Mechanism studies support a non-radical process and H2O acts as the hydrogen donor.
Regioselective Hydroxylation of Stilbenes by Engineered Cytochrome P450 from Thermobifida fusca YX
Rühlmann, Ansgar,Antovic, Dragutin,Müller, Thomas J. J.,Urlacher, Vlada B.
, p. 984 - 994 (2017/03/27)
Since the past decades, the plant stilbenoid resveratrol has gained significant attention of the general public as well as the research community due to its versatile medicinal properties. Apart from resveratrol, there is also an increasing interest in other plant stilbenoids because of their different potential biological activities. In order to meet the increasing demand for stilbenoids, alternative and sustainable approaches for their production are needed. We identified the cytochrome P450 monooxygenase 154E1 from Thermobifida fusca YX (CYP154E1) which enables the synthesis of (E)-4,4′-dihydroxystilbene via direct double hydroxylation of (E)-stilbene. The construction of a triple mutant led to a more than six-fold increased catalytic efficiency compared to the wild type enzyme. CYP154E1 and variants thereof accepted not only (E)-stilbene but also possessed remarkable activity towards ortho- and meta-substituted hydroxystilbenes leading to resveratrol, (E)-2,4′-dihydroxystilbene, (E)-2,4′,5-trihydroxystilbene and (E)-3,4′-dihydroxystilbene. The combination of protein engineering and the use of methyl-β-cyclodextrin as substrate solubilizing agent resulted in product titers of up to 4.2 g L?1 and enzyme total turnover numbers (TTN) of up to 20,000. (Figure presented.).
