Z-Selective semihydrogenation of alkynes via Ni/Lewis acid synergistic catalyzed system using DMF as hydrogen source and solvent

• Lei Kang,
• Haifeng Gao and
• Luo Yang

Beilstein J. Org. Chem. 2026, 22, 1004–1012, doi:10.3762/bjoc.22.79

• Z-olefins. Beyond expanding the toolbox for stereocontrolled alkyne semihydrogenation, this study offers fresh perspectives on the design of Lewis acid–metal synergistic catalytic systems. Results and Discussion We began by developing a base metal catalytic system for the semihydrogenation of

• . Overall, this work provides a practical and cost-effective alternative to existing semihydrogenation methods and highlights the potential of base metal synergistic catalysis in stereocontrolled synthetic transformations. Experimental All experiments were performed under air. An oven-dried reaction vessel

Cu–Bpin-mediated dimerization of 4,4-dichloro-2-butenoic acid derivatives enables the synthesis of densely functionalized cyclopropanes

• Patricia Gómez-Roibás,
• Andrea Chaves-Pouso and
• Martín Fañanás-Mastral

Beilstein J. Org. Chem. 2025, 21, 877–883, doi:10.3762/bjoc.21.71

• the base metal cation. Gratifyingly, we observed that the use of LiOt-Bu led to the formation of product 2 as a single diastereomer (Table 1, entry 5). A slightly lower diastereoselectivity was observed when KOt-Bu was used, which also gave rise to 2 in diminished yield (Table 1, entry 6). The nature

• second molecule of the 4,4-dichloro-2-butenoic acid derivative. We have observed that the use of lithium as base metal cation is key to achieve excellent levels of diastereoselectivity. Our study also highlights, how the dimerization products can be selectively converted into different densely

Visible-light-promoted radical cyclisation of unactivated alkenes in benzimidazoles: synthesis of difluoromethyl- and aryldifluoromethyl-substituted polycyclic imidazoles

• Yujun Pang,
• Jinglan Yan,
• Nawaf Al-Maharik,
• Qian Zhang,
• Zeguo Fang and
• Dong Li

Beilstein J. Org. Chem. 2025, 21, 234–241, doi:10.3762/bjoc.21.15

• CF2HCO2H or PhCF2COOH, along with benzimidazoles bearing unactivated alkenes and PhI(OAc)2 as substrates, and proceeded without the need of any base, metal catalyst, photocatalyst or additive. In total, 24 examples were examined, and all of them successfully underwent cyclization reaction to produce the

Advances in the use of metal-free tetrapyrrolic macrocycles as catalysts

• Mandeep K. Chahal

Beilstein J. Org. Chem. 2024, 20, 3085–3112, doi:10.3762/bjoc.20.257

• with porphyrins, the direct linkage between their pyrrole units leads to a more contracted cavity compared to that of porphyrins. Similar to calix[4]pyrroles, synthetic metallo- and free-base (metal-free) porphyrins find various applications in the fields of medicine, energy, catalysis, molecular

Recent advances in Cu-catalyzed C(sp³)–Si and C(sp³)–B bond formation

• Balaram S. Takale,
• Ruchita R. Thakore,
• Elham Etemadi-Davan and
• Bruce H. Lipshutz

Beilstein J. Org. Chem. 2020, 16, 691–737, doi:10.3762/bjoc.16.67

Copper-mediated arylation with arylboronic acids: Facile and modular synthesis of triarylmethanes

• H. Surya Prakash Rao and
• A. Veera Bhadra Rao

Beilstein J. Org. Chem. 2016, 12, 496–504, doi:10.3762/bjoc.12.49

• report a copper(II) triflate-catalyzed modular synthesis of triarylmethanes by employing diarylmethanols 9 and arylboronic acids 10. It is advantageous to employ a base metal catalyst such as copper(II) triflate instead of palladium [55][56] or nickel (Ni) [57] catalysts and to avoid the use of phosphine

Base metal-catalyzed benzylic oxidation of (aryl)(heteroaryl)methanes with molecular oxygen

• Hans Sterckx,
• Johan De Houwer,
• Carl Mensch,
• Wouter Herrebout,
• Kourosch Abbaspour Tehrani and
• Bert U. W. Maes

Beilstein J. Org. Chem. 2016, 12, 144–153, doi:10.3762/bjoc.12.16

• drug Mefloquine. The oxidation method can also be used to prepare metabolites of APIs which is illustrated for the natural product papaverine. ICP–MS analysis of the purified reaction products revealed that the base metal impurity was well below the regulatory limit. Keywords: base metal; benzylic

• occurred and (6-methylpyridin-2-yl)(p-tolyl)methanone (19b) was isolated in 64% yield as the sole product. These results demonstrate that the oxidation power of the catalytic system can be tuned by careful selection of the solvent as well as the base metal. Conclusion This work shows that the oxidation

• -benzylpyridines (1).a Iron and copper-catalyzed aerobic oxidation of pyridine-substituted 2-benzylpyridines (3).a The influence of the purification method on the amount of Fe impurities in papaveraldine (15) after oxidation. An extended solvent screening for the base metal-catalyzed aerobic oxidation reaction.a

Self-assembly of heteroleptic dinuclear metallosupramolecular kites from multivalent ligands via social self-sorting

• Christian Benkhäuser and
• Arne Lützen

Beilstein J. Org. Chem. 2015, 11, 693–700, doi:10.3762/bjoc.11.79

Preparation of phosphines through C–P bond formation

• Iris Wauters,
• Wouter Debrouwer and
• Christian V. Stevens

Beilstein J. Org. Chem. 2014, 10, 1064–1096, doi:10.3762/bjoc.10.106

• or alkenes bearing no hydrogen on the double bond. Additionally, due to the absence of small rings containing a triple bond, no cyclic alkenylphosphines are accessible. Until now, the protocols lack sufficient control over selectivity and mostly give mixtures. Most addition products (radical, base

• , metal) are anti-Markovnikov 127, only a few palladium catalyzed reactions give the Markovnikov products 126. Several reviews on hydrophosphination of alkynes have been published [90][91][237]. Some recent developments will be discussed. In recent years research has mainly focused on metal-catalyzed