Synthesis of π-conjugated polycyclic compounds by late-stage extrusion of chalcogen fragments

• Aissam Okba,
• Pablo Simón Marqués,
• Kyohei Matsuo,
• Naoki Aratani,
• Hiroko Yamada,
• Gwénaël Rapenne and
• Claire Kammerer

Beilstein J. Org. Chem. 2024, 20, 287–305, doi:10.3762/bjoc.20.30

• % yield. At that stage, the initial ring size of precursor 51 was recovered, and two further steps including a McMurry reaction and a thermolysis were then necessary to obtain endohedral fullerene (H2)n@54. As seen in the two first parts of this review, synthetic strategies involving a late-stage ring

Effect of ring size on photoisomerization properties of stiff stilbene macrocycles

• Sandra Olsson,
• Óscar Benito Pérez,
• Magnus Blom and
• Adolf Gogoll

Beilstein J. Org. Chem. 2019, 15, 2408–2418, doi:10.3762/bjoc.15.233

• units are then attached to an n-alkanediyl linker using a Williamson ether synthesis to yield the diethers 6a–d. Finally, the stiff stilbene unit is formed by an intramolecular McMurry reaction resulting in 1a–d [25][26]. The Z-isomer is formed in huge excess in these reactions and any trace amounts of

A novel application of 2-silylated 1,3-dithiolanes for the synthesis of aryl/hetaryl-substituted ethenes and dibenzofulvenes

• Grzegorz Mlostoń,
• Paulina Pipiak,
• Róża Hamera-Fałdyga and
• Heinz Heimgartner

Beilstein J. Org. Chem. 2017, 13, 1900–1906, doi:10.3762/bjoc.13.185

• . The development of methods for the synthesis of substituted ethenes is of great importance and the so-called olefination reactions allow for valuable functional-group transformations [10][11][12][13]. As a general method for the preparation of tetrasubstituted ethenes, the McMurry reaction is widely

Selected synthetic strategies to cyclophanes

• Sambasivarao Kotha,
• Mukesh E. Shirbhate and
• Gopalkrushna T. Waghule

Beilstein J. Org. Chem. 2015, 11, 1274–1331, doi:10.3762/bjoc.11.142

• synthesis of polyunsaturated [10]paracyclophane annulated by two azulene rings by using the McMurry reaction [100][101]. The bis(trimethylsilyl)enol ether 74 was reacted with 3-methoxycarbonyl-2H-cyclohepta[b]furan-2-one (75) in refluxing decaline to generate the 1,4-diazulenobenzene derivative 76. Double

• %, Scheme 12). In another occasion, Rajakumar and co-workers [102] have synthesized a series of stilbenophanes (e.g., 81) involving N-arylated carbazole moieties possessing small and large cavities. The precursor 80 required for the McMurry reaction was synthesized by the N-arylation of carbazole with the

• Park [112] have synthesized various orthocyclophanes 93 which were further converted into spirobicyclic polyketals with a 2n-crown-n-moiety. Lee and co-workers [113] also reported the synthesis of bicyclic bis-cyclophane 94 by using the McMurry reaction as a key step. Oda and co-workers [114] have

Ring strain and total syntheses of modified macrocycles of the isoplagiochin type

• Andreas Speicher,
• Timo Backes,
• Kerstin Hesidens and
• Jürgen Kolz

Beilstein J. Org. Chem. 2009, 5, No. 71, doi:10.3762/bjoc.5.71

• of isoplagiochin C (1), however failed in this case. This might be due to the enhanced ring strain. Since the McMurry reaction would provide more rigorous conditions for the formation of ring-strained frameworks, the hydroxyaldehyde 27 was oxidized to the dialdehyde 28. It is worth mentioning that 28

• was obligatory to prevent exclusive pinacolborane reduction. ddppf: 1,1′-bis(diphenylphosphino)ferrocene. Synthesis of the tolane precursors 27 and 28 for cyclization. Synthesis of the modified macrocycles 5–7 from the dialdehyde precursors 28–30. Synthesis of the known macrocycle 3 via McMurry

• reaction. AM1 energies [18], angular strain and torsion stress of different modified macrocycles of the isoplagiochin type. Supporting Information Supporting Information File 110: Full experimental details and characterization data.

The efficient synthesis of dibenzo[d,d′]benzo[1,2-b:4,3-b′]dithiophene and cyclopenta[1,2-b:4,3-b′]bis(benzo[d]thiophen)-6-one

• Zhihua Wang,
• Sheng Zhu,
• Jianwu Shi and
• Hua Wang

Beilstein J. Org. Chem. 2009, 5, No. 55, doi:10.3762/bjoc.5.55

• ] as starting material, dibenzo[d,d′]benzo[1,2-b:4,3-b′]dithiophene, a [5]heterohelicene, was synthesized efficiently in 60% yield via formylation and McMurry reaction. Cyclopenta[1,2-b:4,3-b′]bis(benzo[d]thiophen)-6-one, another interesting helical ketone, was also prepared in 79% yield via

• [1,2-b:4,3-b′]dithiophene; McMurry reaction; preparation; Introduction With considerable environmental stability and flexibility in synthesis, π-extended heteroarenes containing thiophene rings within an polyaromatic ring system are currently of great interest because they can potentially be used to

• starting material, formylation and McMurry reaction were employed for preparing 1. The formylation step involves sequential deprotonation of 3 and treatment of the intermediate dilithiated species with N,N-dimethylformamide (DMF). Attempted generation of dilithiated 3 with either lithium diisopropylamide