The [4 + 4] thermocyclization of 9-anthraldehyde: synthesis, crystal structure, experimental and theoretical UV spectra, natural bonding orbital analysis and prediction of third-order nonlinear optical properties

Article abstract of DOI:10.1107/S2053229618003534

The dimer of 9-anthraldehyde, namely heptacyclo[8.6.6.6^2,9.0^3,8.0^11,16.0^17,22.0^23,28]octacosa-3,5,7,11,13,15,17(22),18,20,23(28),24,26-dodecaene-1,9-carbaldehyde, C₃₀H₂₀O₂, has been synthesized by refluxing an ethanol solution in the presence of M(ClO₄)₂ and 1,3-diaminopropan-2-ol (M = Co²⁺ or Cu²⁺). Its structure has been determined by single-crystal X-ray diffraction, showing it to be a new polymorph, referred to as polymorph II, in the monoclinic space group P2₁/n. It is compared with the previously reported triclinic modification [Ehrenberg (1968). Acta Cryst. B24, 1123–1125], which is referred to as polymorph I. The asymmetric unit of polymorph II contains two half molecules located on crystallographic centres, while the asymmetric unit of polymorph I includes one half molecule, also located on a crystallographic centre. Time-dependent density functional theory (TD-DFT) at the RB3LYP level using the 6-31G(d,p) basis set was applied. The predicted electronic absorption spectrum is in good agreement with the experimental one. The analysis of the calculated electronic absorption spectrum of polymorph II was carried out in order to assign the observed electronic transitions and to determine their character. A natural bonding orbital (NBO) analysis was executed at the same level to evaluate charge-transfer, intramolecular hydrogen-bonding interactions and hyperconjugative interactions. The third-order nonlinear optical (NLO) properties of the compound were appraised by the ZINDO/sum-over-states method in both static and dynamic states. The orientationally averaged (isotropic) value of γ for the compound is greater than the corresponding value of 4-nitroaniline (pNA).

Full text of DOI:10.1107/S2053229618003534

Acta Cryst. (2018). C74, doi:10.1107/S2053229618003534
Supporting information
Volume 74 (2018)
Supporting information for article:
The [4 + 4] thermocyclization of 9-anthraldehyde: synthesis, crystal
structure, experimental and theoretical UV spectra, natural bonding
orbital analysis and prediction of third-order nonlinear optical
properties
Seyed Amir Zarei, Keivan Akhtari, Mohammad Piltan, Shaaban M. Kamel and
Joel T. Mague

Acta Cryst. (2018). C74, doi:10.1107/S2053229618003534
Supporting information, sup-1
Table 1S
Selected bond lengths (Å), bond and torsion angles (°) of the dimer compound.
Bond lengths
C(1)-C(8)
1.602(3)
1.529(3)
1.528(3)
1.395(3)
1.393(3)
1.402(3)
C(16)-C(23)
C(16)-C(30)
C(16)-C(17)
C(17)-C(18)
C(19)-C(20)
C(17)-C(22)
1.602(3)
1.531(3)
1.535(3)
1.397(3)
1.381(3)
1.404(3)
C(1)-C(15)
C(1)-C(2)
C(2)-C(3)
C(4)-C(5)
C(2)-C(7)
Bond angles
C(1)-C(15)-O(1)
C(15)-C(1)-C(8)
C(15)-C(1)-C(2)
C(15)-C(1)-C(14)
C(1)-C(2)-C(7)
C(7)-C(2)-C(3)
C(1)-C(2)-C(3)
Torsion angles
O(1)-C(15)-C(1)-C(8)
O(1)-C(15)-C(1)-C(2)
O(1)-C(15)-C(1)-C(14)
125.5(2)
C(16)-C(30)-O(2)
C(30)-C(16)-C(23)
C(30)-C(16)-C(17)
C(30)-C(16)-C(29)
C(16)-C(17)-C(22)
C(22)-C(17)-C(18)
125.5(2)
110.76(15)
108.81(16)
107.06(16)
116.81(17)
119.77(18)
123.39(17)
110.87(16)
106.86(15)
108.11(15)
117.31(16)
119.18(18)
C(16)-C(17)-C(18)
123.51(17)
7.1(3)
O(2)-C(30)-C(16)-C(23) 7.2(3)
O(2)-C(30)-C(16)-C(29) 129.5(2)
O(2)-C(30)-C(16)-C(17) -115.7(2)
130.3(2)
-114.3(2)

Acta Cryst. (2018). C74, doi:10.1107/S2053229618003534
Supporting information, sup-2
-
6.809008 eV
-6.779076 eV
HOMO-4
-6.515674 eV
HOMO-1
-5.880569 eV
HOMO
HOMO-5
-
0.900412 eV
-0.808439 eV
LUMO+1
-0.271021 eV
LUMO+4
-0.141769 eV
LUMO+5
-0.100408 eV
LUMO+6
LUMO
Figure 1S
Molecular
orbital
diagram
of
the
compound
involved
in
the dominant electron transitions along with their molecular orbital energies.
Table 2S
The selected hyperconjugative interactions of the compound along with their stabilization energies (kcal
−
1
mol ) calculated by DFT/RB3LYP/6-31G(d,p).
(
2)
Donor NBO
C17‒C18
C17‒C18
C17‒C18
C17‒C18
C17‒C22
C17‒C22
C18‒H18
C18‒H18
C18‒C19
C18‒C19
Acceptor NBO
C17‒C22
C16‒C23
C19‒C20
C21‒C22
C17‒C18
C21‒C22
C17‒C22
C19‒C20
C16‒C17
C17‒C18
Interaction
σ→σ*
π→σ*
π→π*
π→π*
σ→σ*
σ→σ*
σ→σ*
σ→σ*
σ→σ*
σ→σ*
E
4.60
3.79
19.54
20..03
3.92
3.70
4.19
3.17
4.45
3.48

Acta Cryst. (2018). C74, doi:10.1107/S2053229618003534
Supporting information, sup-3
C19‒H19
C19‒H19
C19‒C20
C19‒C20
C20‒H20
C20‒H20
C20‒C21
C20‒C21
C21‒H21
C21‒H21
C21‒C22
C21‒C22
C21‒C22
C21‒C22
C23‒H23
C23‒C24
C23‒C24
LP(2)O2
LP(2)O2
C17‒C18
C20‒C21
C17‒C18
C21-C22
C18‒C19
C21‒C22
C21‒C22
C22‒C23
C17‒C22
C19-C20
C16-C17
C17-C22
C17‒C18
C19‒C20
C17‒C22
C24‒C29
C28‒C29
C16‒C30
C30‒H30
σ→σ*
σ→σ*
π→π*
π→π*
σ→σ*
σ→σ*
σ→σ*
σ→σ*
σ→σ*
σ→σ*
σ→σ*
σ→σ*
π→π*
π→π*
σ→σ*
σ→σ*
σ→σ*
n→σ*
n→σ*
3.76
3.69
19.48
18.78
3.77
3.61
3.19
4.08
4.53
3.23
3.18
4.48
19.98
20.54
3.44
3.51
3.01
22.47
17.05