Harnessing the versatility of hydrazones through electrosynthetic oxidative transformations

• Aurélie Claraz

Beilstein J. Org. Chem. 2024, 20, 1988–2004, doi:10.3762/bjoc.20.175

• have been harnessed as valuable intermediates in Wolff–Kishner reduction reactions [12][13][14] or for the synthesis of various olefins via diazo or vinyllithium intermediates in the Bamford–Stevens reaction [15] and Shapiro reaction [16], respectively [17]. SAMP/RAMP ((S)/(R)-1-amino-2

Multi-redox indenofluorene chromophores incorporating dithiafulvene donor and ene/enediyne acceptor units

• Christina Schøttler,
• Kasper Lund-Rasmussen,
• Line Broløs,
• Philip Vinterberg,
• Ema Bazikova,
• Viktor B. R. Pedersen and
• Mogens Brøndsted Nielsen

Beilstein J. Org. Chem. 2024, 20, 59–73, doi:10.3762/bjoc.20.8

• therefore it was not possible to determine the purity of the product by this method. In an initial attempt to investigate other synthetic pathways to extended IF compounds, the reduced IF 29 was synthesized from IF dione 1 by a Wolff–Kishner reduction of the two ketones as shown in Scheme 6. Compound 29

Synthetic terpenoids in the world of fragrances: Iso E Super^® is the showcase

• Alexey Stepanyuk and
• Andreas Kirschning

Beilstein J. Org. Chem. 2019, 15, 2590–2602, doi:10.3762/bjoc.15.252

• transformed into cyclohexene 48 with shifted olefinic group by means of a reductive variant of the Wolff–Kishner deoxygenation. A straightforward four-step sequence finally yielded Iso E Super Plus® ((+)-34). Industrially pursued syntheses do not involve a specific stereoinducing step. In fact, it is

One hundred years of benzotropone chemistry

• Arif Dastan,
• Haydar Kilic and
• Nurullah Saracoglu

Beilstein J. Org. Chem. 2018, 14, 1120–1180, doi:10.3762/bjoc.14.98

Latest development in the synthesis of ursodeoxycholic acid (UDCA): a critical review

• Fabio Tonin and
• Isabel W. C. E. Arends

Beilstein J. Org. Chem. 2018, 14, 470–483, doi:10.3762/bjoc.14.33

• oxidized in position C12 to the corresponding ketone, after which Wolff–Kishner reduction can be applied. This whole sequence comprises 5 steps [13]. After the protection of the carboxylic group by acid-catalyzed esterification (quantitative yield), the 3- and 7-OH groups are protected selectively with

• acetic anhydride and pyridine (yield 92%). The 12-OH group is oxidized with CrO3 (yield 98%) and, after a deprotection step in alkaline environment, the formed ketone group can be removed by a Wolff–Kishner reaction yielding CDCA (yield 82%). The overall yield of the dehydroxylation step is around 65

• %. Wolff–Kishner reduction The Wolff–Kishner reaction is widely used by chemists to remove carbonyl moieties yielding unsubstituted alkyl chains. The reaction requires two steps: the hydrazine first reacts with the ketone forming a hydrazone; The addition of a strong base and heat then promote a

Hydroquinone–pyrrole dyads with varied linkers

• Hao Huang,
• Christoffer Karlsson,
• Maria Strømme,
• Martin Sjödin and
• Adolf Gogoll

Beilstein J. Org. Chem. 2016, 12, 89–96, doi:10.3762/bjoc.12.10

• . achieved a total yield of 70% [11], however, their procedure relies on a Wolff–Kishner reduction of the corresponding acylpyrrole with hydrazine hydrate, making it impractical in countries where the use of hydrazine has been restricted by law [12]. As an alternative, the Suzuki–Miyaura reaction can be

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

• accomplished in a one-pot reaction under Wolff–Kishner reaction conditions to generate 223 and 259, respectively (Scheme 41). Cycloaddition reactions [2 + 2] Cycloaddition: Roemer and Lentz [175] have reported the synthesis of fluorinated ferrocenophanes from 1,10-bis(trifluorovinyl)ferrocene and 1,4-(1,10

Substrate dependent reaction channels of the Wolff–Kishner reduction reaction: A theoretical study

• Shinichi Yamabe,
• Guixiang Zeng,
• Wei Guan and
• Shigeyoshi Sakaki

Beilstein J. Org. Chem. 2014, 10, 259–270, doi:10.3762/bjoc.10.21

• Shinichi Yamabe Guixiang Zeng Wei Guan Shigeyoshi Sakaki Fukui Institute for Fundamental Chemistry, Kyoto University, Takano-Nishihiraki-cho 34-4, Sakyo-ku, Kyoto 606-8103, JAPAN. Phone: +81-075-711-7907 10.3762/bjoc.10.21 Abstract Wolff–Kishner reduction reactions were investigated by DFT

• product. For both ketone substrates, the diimines undergoing E2 reactions were found to be key intermediates. Keywords: acetone; acetophenone; DFT calculations; diimine intermediate; reduction reaction; transition states; Wolff–Kishner; Introduction The Wolff–Kishner (W-K) reduction is an organic

• * calculations [45] were carried out on the precursor and the rate-determining step. All the calculations were carried out using the GAUSSIAN 09 program package [46]. The computations were performed at the Research Center for Computational Science, Okazaki, Japan. Geometric changes of the neutral Wolff–Kishner

Recent applications of the divinylcyclopropane–cycloheptadiene rearrangement in organic synthesis

• Sebastian Krüger and
• Tanja Gaich

Beilstein J. Org. Chem. 2014, 10, 163–193, doi:10.3762/bjoc.10.14

• achieved by the conjugate addition of cyanide [78]. Reduction of the newly introduced nitrile yielded the unexpected stable pentacycle 77. Formation of the missing methyl group (compound 78) could be achieved using forcing Wolff–Kishner-conditions. Benzoate formation and global oxidation [79][80] finally