Sigmatropic rearrangements of cyclopropenylcarbinol derivatives. Access to diversely substituted alkylidenecyclopropanes

• Guillaume Ernouf,
• Jean-Louis Brayer,
• Christophe Meyer and
• Janine Cossy

Beilstein J. Org. Chem. 2019, 15, 333–350, doi:10.3762/bjoc.15.29

• substrate scope and some applications of the products arising from those reactions, are presented in this review. Keywords: alkylidenecyclopropanes; cyclopropanes; cyclopropenes; sigmatropic rearrangements; strained rings; Introduction Among the ever expanding diversity of chemical transformations

Selective ring-opening metathesis polymerization (ROMP) of cyclobutenes. Unsymmetrical ladderphane containing polycyclobutene and polynorbornene strands

• Yuan-Zhen Ke,
• Shou-Ling Huang,
• Guoqiao Lai and
• Tien-Yau Luh

Beilstein J. Org. Chem. 2019, 15, 44–51, doi:10.3762/bjoc.15.4

• different polymeric backbones [21][22]. It seems to be not easy if both strands are arisen from different strained rings by ROMP. It is known that norbornenes having different substituents would have different reaction rates in ROMP [23]. These discrepancies in reactivity have been used for sequence control

Three new trixane glycosides obtained from the leaves of Jungia sellowii Less. using centrifugal partition chromatography

• Luíse Azevedo,
• Larissa Faqueti,
• Marina Kritsanida,
• Antonia Efstathiou,
• Despina Smirlis,
• Gilberto C. Franchi Jr,
• Grégory Genta-Jouve,
• Sylvie Michel,
• Louis P. Sandjo,
• Raphaël Grougnet and
• Maique W. Biavatti

Beilstein J. Org. Chem. 2016, 12, 674–683, doi:10.3762/bjoc.12.68

• four strained rings in the trixane skeleton, explaining their downfield resonances. COSY correlations (Figure 3) revealed from H-10 (δ 2.12) to H-9 (δ 1.63, 1.69), H-9 to H-8 (δ 1.58, 2.00), H-8 to H-7 (δ 2.11) which in turn correlated with H-14 (δ 4.04, 4.17) in addition to the HMBC correlations

Synthetic applications of gold-catalyzed ring expansions

• David Garayalde and
• Cristina Nevado

Beilstein J. Org. Chem. 2011, 7, 767–780, doi:10.3762/bjoc.7.87

• David Garayalde Cristina Nevado Organic Chemistry Institute, University of Zürich, Winterthurerstr. 190, CH-8057, Zürich, Switzerland 10.3762/bjoc.7.87 Abstract The development of new methodologies catalyzed by late transition metals involving cycloisomerizations of strained rings can open new

• ; ring expansion; strained rings; Introduction Over the past twenty years, the image of gold has evolved, from being considered a dead-entity in terms of chemical reactivity, to playing a key role in catalytic processes. The vast array of gold-mediated transformations reported so far share a common

• powerful in triggering ring-expansion processes to introduce structural complexity into organic molecules. The gold-catalyzed ring expansion of strained rings is viewed nowadays as a flexible synthetic tool in organic synthesis [7][8][9]. In this review, we aim to summarize the most recent developments in