Strategies to access the [5-8] bicyclic core encountered in the sesquiterpene, diterpene and sesterterpene series

• Cécile Alleman,
• Charlène Gadais,
• Laurent Legentil and
• François-Hugues Porée

Beilstein J. Org. Chem. 2023, 19, 245–281, doi:10.3762/bjoc.19.23

• construction of the 8-membered ring from an appropriate cyclopentane precursor. The proposed strategies include metathesis, Nozaki–Hiyama–Kishi (NHK) cyclization, Pd-mediated cyclization, radical cyclization, Pauson–Khand reaction, Lewis acid-promoted cyclization, rearrangement, cycloaddition and biocatalysis

• precursor. The proposed strategies include metathesis, Nozaki–Hiyama–Kishi (NHK) cyclization, Pd-mediated cyclization, radical cyclization (including SmI2), Pauson–Khand reaction, Lewis acid-promoted cyclization, rearrangement, cycloaddition, and biocatalysis. In particular, the purpose will focus on the

• electrophilic desilylation agents which can be used, a large diversity of compounds can be accessible through this method [51][52]. Oxidation followed by desilylation with fluoride source produces the natural product poitediol (118) in overall good yield. 2 Nozaki–Hiyama–Kishi (NHK) cyclization The Nozaki

Three-component coupling of aryl iodides, allenes, and aldehydes catalyzed by a Co/Cr-hybrid catalyst

• Kimihiro Komeyama,
• Shunsuke Sakiyama,
• Kento Iwashita,
• Itaru Osaka and
• Ken Takaki

Beilstein J. Org. Chem. 2018, 14, 1413–1420, doi:10.3762/bjoc.14.118

• substituted secondary alcohols, as demonstrated in the Nozaki–Hiyama–Kishi (NHK) reaction (Scheme 2) [4][5][6][7][8][9]. Although the catalyst combination allows the use of organic halides as carbon nucleophiles, a multicomponent coupling reaction using a similar catalyst combination has had limited success

• characters of organometallics depending on the central metals. Ni/Cr or Co/Cr-catalyzed NHK reaction. Functionalization of alkynes via carbocobaltation. Cyclization/borylation of alkynyl iodoarenes using the Co/Cr catalyst. Three-component coupling of aryl iodides, arenes, and aldehydes using Co/Cr catalyst

Efficient syntheses of 25,26-dihydrodictyostatin and 25,26-dihydro-6-epi-dictyostatin, two potent new microtubule-stabilizing agents

• María Jiménez,
• Wei Zhu,
• Andreas Vogt,
• Billy W. Day and
• Dennis P. Curran

Beilstein J. Org. Chem. 2011, 7, 1372–1378, doi:10.3762/bjoc.7.161

• ; microtubules; NHK; Introduction The discovery of compounds that function as anticancer agents by altering the dynamics of microtubules continues to be an important goal in medicinal chemistry. Such agents can force the cell to exit mitosis aberrantly, leading to apoptosis [1][2]. Important classes of

• ) reaction sequence to give 5 [8][9]. The bottom fragment 6a or 6b was then attached to the top/middle fragment 5 through an esterification reaction. Finally, an intramolecular Nozaki–Hiyama–Kishi (NHK) reaction [31][32] of compounds 4a and 4b was used to form the macrolactone at C9–C10. We have previously

• chromatography. Selective deprotection of purified 24b with HF·pyridine afforded the respective primary alcohol 25b in 84% yield. Next, treatment of each primary alcohol 25a,b with Dess–Martin reagent provided aldehydes 4a and 4b in comparable yields (95% and 94%). Initial NHK reactions were performed in THF