Remarkably Slow Rotation about a Single Bond between an sp3-Hybridised Carbon Atom and an Aromatic Ring withoutorthoSubstituents

2009 ◽  
Vol 15 (9) ◽  
pp. 2185-2189 ◽  
Author(s):  
Sarah Murrison ◽  
David Glowacki ◽  
Christian Einzinger ◽  
James Titchmarsh ◽  
Stephen Bartlett ◽  
...  
Keyword(s):  
Carbon Atom ◽  
Aromatic Ring ◽  
Slow Rotation ◽  
Single Bond

scholarly journals Ester Dance Reaction on the Aromatic Ring

2019 ◽  
Author(s):  
Kaoru Matsushita ◽  
Ryosuke Takise ◽  
Kei Muto ◽  
Junichiro Yamaguchi
Keyword(s):  
Carbon Atom ◽  
Aromatic Ring ◽  
Functional Group ◽  
State Of The Art ◽  
Palladium Catalysis ◽  
Ester Group ◽  
Halogen Atoms ◽  
Ester Moiety ◽  
Rearrangement Reactions ◽  
Halogen Dance Reaction

Aromatic rearrangement reactions are useful tools in the organic chemist’s toolbox when generating uncommon substitution patterns. However, it is difficult to precisely translocate a functional group in (hetero)arene systems, with the exception of halogen atoms in a halogen dance reaction. Herein, we describe an unprecedented “ester dance” reaction: a predictable translocation of an ester group from one carbon atom to another on an aromatic ring. Specifically, a phenyl carboxylate substituent can be shifted from one carbon to an adjacent carbon on a (hetero)aromatic ring under palladium catalysis to often give a thermodynamically favored, regioisomeric product with modest to good conversions. The obtained ester moiety can be further converted to various aromatic derivatives through the use of classic as well as state-of-the-art transformations including an amidation, acylations and decarbonylative couplings.

Notizen: Cyclophanes, XXX The Crystal Structure of [2.4]Paracyclophane at —95°C

1989 ◽  
Vol 44 (7) ◽  
pp. 860-862 ◽  
Author(s):  
Peter G. Jones ◽  
Zissis Pechlivanidis ◽  
Henning Hopf
Keyword(s):  
Crystal Structure ◽  
Bond Length ◽  
Aromatic Ring ◽  
Single Bond ◽  
Orthorhombic Space Group ◽  
Ring Systems ◽  
Space Group ◽  
Benzylic Carbon ◽  
Central Bond

[2.4]Paracyclophane crystallizes in the orthorhombic space group Pbca with cell constants (at —95°C) a = 1151.5(5), b = 1832.9(7), c = 1304.1(4) pm. The structure was refined to R = 0.053 for 1626 unique observed reflections. The aromatic ring systems are inclined to each other at an angle of 21°. The longer bridge is capable of more relaxation than the shorter, as is reflected in the non-bonded distances 279, 386 pm between bridgehead atoms and in the smaller displacements of the associated benzylic carbon atoms from the aromatic ring planes. The central bond length of the longer bridge (151.8 pm) is shorter than would be expected for a single bond.

scholarly journals Studies on the biosynthesis of phenols in fungi. Production of 4-methoxytoluquinol, epoxysuccinic acid and a diacetylenic alcohol by surface cultures of Lentinus degener I.M.I. 110525

1969 ◽  
Vol 114 (2) ◽  
pp. 369-377 ◽  
Author(s):  
N. M. Packter
Keyword(s):  
Salicylic Acid ◽  
Carbon Atom ◽  
Aromatic Ring ◽  
Early Phase ◽  
Culture Medium ◽  
Methyl Group ◽  
Maximum Production ◽  
Diacetylenic Alcohol ◽  
Fungi Imperfecti ◽  
Long Chain

1. 4-Methoxytoluquinol was secreted into the medium by surface cultures of the basidiomycete Lentinus degener Kalchbr. (approx. 100mg./l. of medium). In addition, epoxysuccinic acid (150–200mg.) and a long-chain diacetylenic alcohol (3mg.) were also secreted. Epoxysuccinic acid has previously been found in the culture medium of some Fungi Imperfecti. These metabolites were all synthesized during the early phase of growth but maximum production occurred some time later. 2. Supplementation of the medium with cycloheximide or 8-azaguanine inhibited the production of epoxysuccinic acid. 3. Sodium [1−14C]acetate and 6-methyl[14C]salicylic acid were not incorporated into 4-methoxytoluquinol, but [U−14C]tyrosine and [Me−14C]methionine were incorporated to the extent of 0·55 and 4·75% respectively (minimum values). Degradation studies established that the aromatic ring and C-methyl group were derived from the ring and β-carbon atom of tyrosine; the O-methyl group alone was formed from methionine.

scholarly journals Crystal structure of 1-butyl-3-{2-[(indan-5-yl)amino]-2-oxoethyl}-1H-imidazol-3-ium chloride

2018 ◽  
Vol 74 (11) ◽  
pp. 1665-1668
Author(s):  
Vidya Zende ◽  
Tejpalsingh Ramsingh Girase ◽  
Nicolas Chrysochos ◽  
Anant Ramakant Kapdi ◽  
Carola Schulzke
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Carbon Atom ◽  
Aromatic Ring ◽  
Methylene Carbon ◽  
Hydrogen Bonding Interactions ◽  
Methylene Carbon Atom ◽  
Molecular Salt

In the cation of the title molecular salt, C18H24N3O+·Cl−, an intramolecular C—H...O hydrogen bond stabilizes the almost coplanar orientation of the aromatic ring of the indane unit and the amide plane. In the crystal, the packing is dominated by intermolecular C—H...Cl hydrogen-bonding interactions that result in the formation of slab-like structures propagating along [010]. The slabs are linked by weak C—H...O interactions, forming layers lying parallel to (100). The methylene carbon atom of the indanyl substituent is disordered over two positions with a refined occupancy ratio of 0.84 (2):0.16 (2). The crystal studied was refined as a twin with matrix [1 0 0.9, 0 \overline{1} 0, 0 0 \overline{1}]; the resulting BASF value is 0.30.

scholarly journals Ester dance reaction on the aromatic ring

2020 ◽  
Vol 6 (28) ◽  
pp. eaba7614
Author(s):  
Kaoru Matsushita ◽  
Ryosuke Takise ◽  
Kei Muto ◽  
Junichiro Yamaguchi
Keyword(s):  
Carbon Atom ◽  
Aromatic Ring ◽  
Functional Group ◽  
State Of The Art ◽  
Palladium Catalysis ◽  
Ester Group ◽  
Halogen Atoms ◽  
Ester Moiety ◽  
Rearrangement Reactions ◽  
Halogen Dance Reaction

Aromatic rearrangement reactions are useful tools in the organic chemist’s toolbox when generating uncommon substitution patterns. However, it is difficult to precisely translocate a functional group in (hetero) arene systems, with the exception of halogen atoms in a halogen dance reaction. Here, we describe an unprecedented “ester dance” reaction: a predictable translocation of an ester group from one carbon atom to another on an aromatic ring. Specifically, a phenyl carboxylate substituent can be shifted from one carbon to an adjacent carbon on a (hetero) aromatic ring under palladium catalysis to often give a thermodynamically favored, regioisomeric product with modest to good conversions. The obtained ester moiety can be further converted to various aromatic derivatives through the use of classic and state-of-the-art transformations including amidation, acylations, and decarbonylative couplings.

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