Anion–π catalysis on carbon allotropes

• M. Ángeles Gutiérrez López,
• Mei-Ling Tan,
• Giacomo Renno,
• Augustina Jozeliūnaitė,
• J. Jonathan Nué-Martinez,
• Javier Lopez-Andarias,
• Naomi Sakai and
• Stefan Matile

Beilstein J. Org. Chem. 2023, 19, 1881–1894, doi:10.3762/bjoc.19.140

• than intrinsic anion–π interactions should provide access to really strong catalysts [3]. They have been predicted theoretically to occur on π-stacks [6], and confirmed recently to exist and apply to anion–π catalysis on π-stacked foldamers (Figure 1B) [7] and micelles [8]. However, due to their unique

• -covalently electrify organic synthesis in the broadest sense. (A) Anion–π catalysis: Stabilization of anionic transition states from substrate S to product P on π-acidic aromatic surfaces. (B) Anion–(π)n–π catalysis: Stabilization of anionic transition states by polarization of π stacks to induce oriented

Introducing a new 7-ring fused diindenone-dithieno[3,2-b:2',3'-d]thiophene unit as a promising component for organic semiconductor materials

• Valentin H. K. Fell,
• Joseph Cameron,
• Alexander L. Kanibolotsky,
• Eman J. Hussien and
• Peter J. Skabara

Beilstein J. Org. Chem. 2022, 18, 944–955, doi:10.3762/bjoc.18.94

• in organic solvents can be achieved [5]. Bulky side chains are more efficient in increasing solubility in comparison to linear alkyl chains, however, bulky or branched side chains also hinder the formation of π–π-stacks. Another problem about alkyl chains is their insulating nature, having an adverse

Synthesis of novel alkynyl imidazopyridinyl selenides: copper-catalyzed tandem selenation of selenium with 2-arylimidazo[1,2-a]pyridines and terminal alkynes

• Mio Matsumura,
• Kaho Tsukada,
• Kiwa Sugimoto,
• Yuki Murata and
• Shuji Yasuike

Beilstein J. Org. Chem. 2022, 18, 863–871, doi:10.3762/bjoc.18.87

• torsion angle of 10.28°. 2-Phenylimidazo[1,2-a]pyridine moieties of neighboring molecules were arranged into slipped-parallel π-stacks with head-to-tail or head-to-head orientations. The distances between parallel mean planes were 3.427 and 3.428 Å (Figure 2b). To demonstrate the efficiency and to broaden

Towards triptycene functionalization and triptycene-linked porphyrin arrays

• Gemma M. Locke,
• Keith J. Flanagan and
• Mathias O. Senge

Beilstein J. Org. Chem. 2020, 16, 763–777, doi:10.3762/bjoc.16.70

• (II)-porphyrin only π-stacks with another Ni(II)-porphyrin at a centroid to mean-plane distance of 3.421(5) Å and a shift of distance of 3.415(8) Å (Figure 4a). The Zn(II)-porphyrin only π-stacks with another Zn(II)-porphyrin at a centroid to mean-plane distance of 3.399(2) Å and a shift distance of

Scalable synthesis of 5,11-diethynylated indeno[1,2-b]fluorene-6,12-diones and exploration of their solid state packing

• Bradley D. Rose,
• Peter J. Santa Maria,
• Aaron G. Fix,
• Chris L. Vonnegut,
• Lev N. Zakharov,
• Sean R. Parkin and
• Michael M. Haley

Beilstein J. Org. Chem. 2014, 10, 2122–2130, doi:10.3762/bjoc.10.219

• molecules form 1-D π-stacks (interplanar spacing 3.446(5) Å) parallel to a, with adjacent stacks having the opposite tilt by virtue of the c-glide, leading to a herringbone motif in which inter-stack interactions are solely between the SiMe3 groups. This is the only structure of this type in the group of

• ten compounds. The next largest (8g, SiMe2PrF3, vol. ~198 Å3) is orthorhombic, Pca21, with a squat unit cell (short b axis). Molecules form 1-D π-stacks parallel to the b-axis (interplanar spacing 3.358(3) Å), while adjacent stacks interact via C-H···π contacts to form herringbone-patterned layers

• form 1-D π-stacks parallel to b (interplanar spacings of 3.454(2) Å, 3.340(2) Å and 3.385(3) Å, respectively, for 8b, 8i and 8h). Adjacent stacks along c interact via C–H···π-contacts, and are related by the c-glide operation to form the common herringbone motif (interstack molecular tilts of 64.88(2

Multistep organic synthesis of modular photosystems

• Naomi Sakai and
• Stefan Matile

Beilstein J. Org. Chem. 2012, 8, 897–904, doi:10.3762/bjoc.8.102

• fill them with functional π-stacks of free choice. Keywords: asparagusic acid; charge-transfer cascades; chromophores; disulfide exchange; hydrazone exchange; molecular switches; naphthalenediimides; π-stacks; surface-initiated polymerization; Introduction The architecture of photosystem 1 is rather

• sophisticated, probably as sophisticated as it gets with photosystems today (Figure 1) [1]. It is composed of three co-axial π-stacks that are grown from an indium tin oxide (ITO) surface. With lower frontier molecular orbital (FMO) levels, the “yellow” stacks can transport photogenerated electrons toward the

Self-assembly and semiconductivity of an oligothiophene supergelator

• Pampa Pratihar,
• Suhrit Ghosh,
• Vladimir Stepanenko,
• Sameer Patwardhan,
• Ferdinand C. Grozema,
• Laurens D. A. Siebbeles and
• Frank Würthner

Beilstein J. Org. Chem. 2010, 6, 1070–1078, doi:10.3762/bjoc.6.122

• mobility value obtained for T1 is very close to that reported for non-regio regular alkyl-substituted polythiophenes (Σμmin = 7 × 10−3 cm2 V−1 s−1) [29], suggesting similar electronic coupling between oligothiophenes in the gelated π-stacks. Conclusion We have demonstrated the self-assembly and charge

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

• . The lack of contact between the π-stacks indicates that the crystal has one-dimensional (1D) electronic structure [13]. UV–vis spectra of 1 and 2 The UV–vis spectra of 1 and 2 in chloroform are shown in Figure 4. 1 shows the main peaks at 323 nm, 335 nm, and 372 nm, and 2 gives two broad peaks at 339