Structure of 1-(Arylselanyl)naphthalenes − Y Dependence in 1-(p-YC6H4Se)C10H7

Bioinorganic Chemistry and Applications

2006

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The orientational effect of p-YC6H4 (Ar) on δ(Se) is elucidated for ArSeR, based on experimental and theoretical investigations. Sets of δ(Se) are proposed for pl and pd employing 9-(arylselanyl)anthracenes (1) and 1-(arylselanyl)anthraquinones (2), respectively, where Se–C R in ArSeR is on the Ar plane in pl and perpendicular to the plane in pd. Absolute magnetic shielding tensors of Se (σ(Se)) are calculated for ArSeR (R = H, Me, and Ph), assuming pl and pd, with the DFT-GIAO method. Observed characters are well reproduced by the total shielding tensors (σ t(Se)). The paramagnetic terms (σ P(Se)) are governed by σ P(Se)xx + σ P(Se)yy, where the direction of nP(Se) is set to the z-axis. The mechanisms of the orientational effect are established both for pl and pd. Sets of δ(Se: 1) and δ(Se: 2) act as the standards for pl and pd, respectively, when δ(Se) of ArSeR are analyzed based on the orientational effect.

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Proposal for Sets of ⁷⁷Se NMR Chemical Shifts in Planar and Perpendicular Orientations of Aryl Group and the Applications

Bioinorganic Chemistry and Applications

2006

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“…Our strategy to construct the extended hypervalent bonds is to employ the interactions caused by direct orbital overlaps between nonbonded atoms [1–11, 19–21]. Weak interactions control fine structures and create delicate functionalities of materials [15, 22–40]. Recently, extended hypervalent bonds are shown to play an important role in physical, chemical and biological properties of the compounds [41–50].…”

Section: Introductionmentioning

confidence: 99%

“…The Y- and G-dependences are also discussed for 8-G-1-( p -YC 6 H 4 Se)C 10 H 6 [ 4 (G = H) [22], 5 (G = Cl) [16], and 6 (G = Br) [16] for convenience of comparison. 1 – 3 are prepared and the structures of some compounds are determined by the X-ray crystallographic analysis.…”

Section: Introductionmentioning

confidence: 99%

“…Structures of the naphthalene system are well explained by the three types, A , B , and C , in our definition, where the Se–C sp 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 [4, 15, 16, 22, 23, 68]. The A , B , and C notations are employed for the structures around the Se–C Nap bonds in 1 – 6 .…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Fine Structures of 8‐G‐1‐(p‐YC₆H₄C ≡ CSe)C₁₀H₆ (G = H, Cl, and Br) in Crystals and Solutions: Ethynyl Influence and Y‐ and G‐Dependences

Yamane

Bioinorganic Chemistry and Applications

2009

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Fine structures of 8-G-1-(p-YC6H4C ≡ CSe)C10H6 [1 (G = H) and 2 (G = Cl): Y = H (a), OMe (b), Me (c), F (d), Cl (e), CN (f), and NO2 (g)] are determined by the X-ray analysis. Structures of 1, 2, and 3 (G = Br) are called A if each Se–Csp bond is perpendicular to the naphthyl plane, whereas they are B when the bond is placed on the plane. Structures are observed as A for 1a–c bearing Y of nonacceptors, whereas they are B for 1e–g with Y of strong acceptors. The change in the structures of 1e–g versus those of 1a–c is called Y-dependence in 1. The Y-dependence is very specific in 1 relative to 1-(p-YC6H4Se)C10H7 (4) due to the ethynyl group: the Y-dependence in 1 is almost inverse to the case of 4 due to the ethynyl group. We call the specific effect “Ethynyl Influence.” Structures of 2 are observed as B: the A-type structure of 1b changes dramatically to B of 2b by G = Cl at the 8-position, which is called G-dependence. The structures of 2 and 3 are examined in solutions based on the NMR parameters.

Recent Advances of Structural Chemistry of Organoselenium and Organotellurium Compounds

Patai's Chemistry of Functional Groups

Hashimoto

et al. 2014

The recent advances of structural chemistry of organoselenium and organotellurium compounds are reviewed. The basic concepts of structural chemistry of the compounds are well summarized in Chapter 3 of Volume 1 in this series. About 9,000 structures for the compounds have been reported since then, therefore only selected results can be discussed here. Such compounds are expected to contain at least one CE (E = Se or Te) bond, although those with no CE bonds are also discussed, as necessary. Compounds containing CE (E = Se and Te) are discussed in some detail. Structures of unstable and/or reactive species are explained in detail, which are stabilized by the formation of dimers or higher oligomers or using large protecting groups. Bis‐selenides and bis‐tellurides and the derivatives at the naphthalene 1,8‐positions and the related systems are discussed in detail. The compounds containing hypervalent interactions are also discussed in detail. The idea is applied to the intramolecular and intermolecular linear interactions in crystals. In this connection, the extended hypervalent interactions are also explained in detail for the linear interactions longer than three, exemplified by typical cases and unique cases in crystals.