How Are Non-Bonded G···Z (Z = O, S, and Se) Distances at Benzene 1,2-, Naphthalene 1,8-, and Anthracene 1,8,9-Positions Controlled? An Approach to Causality in Weak Interactions

Abstract

Mechanisms operating in weak interactions are sometimes quite different from those in strong ones. Factors to control the non-bonded G···Z (Z = O, S, and Se) distances at naphthalene 1,8-positions in 8-G-1-RZC10H6 are analyzed as an example to clarify the causality of weak interactions. Structures around Z in 8-G-1-RZC10H6 are well explained by three types, A, B, and C, where the Z–CR bond is perpendicular to the naphthyl plane in A, it is placed on the plane in B, and C is intermediate between A and B. The r(Z···Z) distances in 1,8-(RZ)2C10H6 are observed to increase in an order of BB < CC < AB < AA. It seems difficult to explain the sequence based on the magnitudes of the closed-shell Z···Z interactions, since the BB interaction must not be so strong especially for Z of heavier atoms. The mechanism to control the r(Z···Z) distances is demonstrated to be the reflection from the repulsive interactions between R and H at the 2-position in 1,8-(RZ)2C10H6. Similar phenomena are also detected in the observed and calculated results at the benzene 1,2-, anthracene 1,8,9-, and anthraquinone 1,8,9-positions, which are explained based on the mechanism. Proposed idea and mechanism will help us to understand what happens in such weak interactions.

Crystal structures of β‐chalcogeno‐α, β‐unsaturated chalcogenoesters: Novel intramolecular interaction between the carbonyl oxygen and the chalcogen atom at the β‐position

“…These results strongly suggest that, in the cases of 1a-1c, the σ *-n interaction between the S-atom of S C C moiety and the carbonyl oxygen contributes to the lower carbonyl wavenumber in IR spectra and the shorter S· · ·O distance [8]. In the case of 1d, however, the nonlinear relationship of C ipso , S, and O and the longer S· · ·O distance indicate lack of such the σ *-n interaction, resulting in the normal IR value of carbonyl wavenumber.…”

“…• C-141 73, 126.66, 127.57, 128.09, 128.33, 128.45, 128.67, 128.93, 129.05, 129.37, 135.79, 136.05, 138.58, 159.57, 187.77;IR (KBr) 3057, 1658, 1531, 1486, 1476, 1437, 1227, 1042 61.33, 115.17, 129.08, 129.50, 129.54, 129.72, 130.25, 135.93, 136.78, 137.35, 137.59, 157.82, 187.97;IR (KBr) 3554, 1637, 1521, 1473, 1438, 1103, 1068, 1037, 1020 (2Z, 8Z)-1,3, 8, mp 114-115…”

Insertion of Benzyne into a Bi–S Bond: A New Synthetic Route to ortho-Functionalized Bismuthanes and Its Application to the Synthesis of Dibenzothiophene

“…Thus, the six heteroatoms, including bismuth, sulfur, and bromine, are linked through weak interactions. This kind of unusual interaction has been observed in ortho -disubstituted benzenes and peri -substituted naphthalene and anthracene . Intermolecular CH−π interactions are present between the H(9) and one of the tolyl groups [C(8)–C(14)] at the bismuth atom.…”

Synthesis of a Novel Cysteine-Incorporated Anthraquinone Derivative and Its Structural Properties

“…In recent times, anthraquinone has been focused on as a functional molecule in photo- or electrochemical moieties, and also has a rigid planar structure at the molecular level [4,5,6,7,8,9,10,11]. Such properties of anthraquinone have been exploited to synthesize functional ligands as metal receptors [12,13,14,15].…”