N. Bera, S. Bardhan, H. Reuter et al.
Journal of Molecular Structure 1243 (2021) 130813
ing, by vanillin stain solution, or by staining with potassium per-
and concentrated under vacuum gave a light yellow dense
liquid. The crude oil was exposed to silica gel column chro-
matography and eluted with ethyl acetate in hexane gave
the desired homopropargylalcohol/homopropargylamine.
Step 2: The homopropargylalcohol/N-protected homopropargy-
lamine [1 eq] was dissolved in dry THF [6 ml] under an inert
atmosphere in a 2 neck round bottle flask and cooled down
to −78ºC in an immersion cooler. To this solution, n-BuLi
[2.2 eq, 2.5 M in hexanes] was added dropwise and stirring
was continued at the same temperature for 1 hour. At this
point, the corresponding aldehyde [1 eq] was added neat,
and the mixture was allowed to attain room temperature
manganate (KMnO ). Silica flash chromatography was performed
4
on 230–400 mesh silica gel and 100–200 mesh silica gel. NMR
spectra were recorded on a Bruker 400 MHz NMR spectrometer in
CDCl . Chemical shifts are expressed in ppm relative to solvent sig-
3
nals, TMS was taken as internal standard CDCl3 (1H, 7.28 ppm, 13C,
7
7.0 ppm) and coupling constants are expressed in Hz. 1H spec-
tral data were reported as δ (multiplicity, Coupling constant, in-
tegration). Multiplicity reported as follows, s = singlet, d = doublet,
t =triplet, q = quartet, m = multiplate, dd = doublet of a doublet
etc. IR spectra were recorded on a Shimadzu FTIR spectrometer
over KBr pellet with peaks reported in cm–1. High-Resolution Mass
Spectra (HRMS) were measured in a QTOF I (quadrupolehexapole-
TOF) mass spectrometer with an orthogonal Z-spray-electrospray
interface on Micro (YA-263) mass spectrometer.
and quenched by adding saturated NH Cl solution. Then the
4
reaction mixture was extracted with DCM and dried over an-
hydrous Na SO . Evaaporated of the organic solvent followed
2
4
by flash chromatography with silica gel afforded the alcohol
(1)/(2).
2
.2. Syntheses
2
.2.1. Synthesis of compound (1)
2.3. X-ray crystal structure determination
[6-methyl-1-(p-tolyl)hept–3–yne-1,5-diol]
Single crystal X-ray diffraction data for compounds (1) and
(
2) were collected by using Bruker APEX-II and Bruker axs kappa
apex2 CCD diffractometer with graphite monochromated MoKα ra-
˚
diation (λ= 0.71073 A) at 100(2)K and 293(2)K respectively. The
program Bruker SAINT [19] was used for the data reduction process
and empirical absorption correction was used based on the multi-
scan method [20]. The structure of the title compounds was solved
by direct method and refined by the full-matrix least-squares tech-
nique on F2 using the programs (SHELXS-14) [21] and (SHELXL-18)
[
22], respectively. The hydrogen atoms were placed at their geo-
metrically idealized positions and refined isotropically. The struc-
ture solution of the title compounds was carried out by using
WinGX program V2014.1 [23] and geometrically analyzed by PLA-
TON [24]. The details of crystal data and structure refinement pa-
rameters are included in Table 1. CCDC 2,044,801 and 2,045,176
contain the supplementary crystallographic data for compounds (1)
and (2) respectively.
2
.2.2. Synthesis of compound (2)
[N-(5–hydroxy-1-phenylhex-3-yn-1-yl)−4-nitrobenzenesulfonamide]
2
.4. Hirshfeld surface analysis
The Hirshfeld surface [25-28] analyses have been performed
based on electron distribution of the molecules that have been cal-
culated as the sum of spherical atom electron densities [29,30].
Hirshfeld surface is unique for each and individual molecule and
a set of spherical atomic electron densities [31]. The normalized
contact distance is called (dnorm) that have been calculated based
on de, di, and the vdW radii of the atom where de and d are de-
i
fined as the distance from the point to the nearest nucleus ex-
ternal and internal to the surface respectively. The 2D fingerprint
plot [31-34] is generated by binning both de and d parameters that
i
display the details of the quantified intermolecular interactions of
the investigating structures. The program CrystalExplorer17 [35] has
been used to perform the Hirshfeld surface calculations.
2
.5. Theoretical methods
General procedure for the synthesis of compounds (1) and (2):
The compounds (1) and (2) are synthesized in a two steps proce-
The wave function analyses have been executed by using Gaus-
dure.
sian09 calculation package [36]. The crystallographic coordinates
have been used for the theoretical calculations. Bader’s “Atoms
in molecules” theory [37] was used to investigate the noncova-
lent interactions by AIMall calculation package [38]. In this calcu-
lation, charge density (ρ(r)) is characterized by their critical points
Step 1: To a well-stirred solution of Zn dust in dry THF at
0
°C, Tolualdehyde/N-protected imine was added under an
inert atmosphere. To this reaction mixture, propargyl bro-
mide was added dropwise. Then the reaction mixture was,
allowed to attain room temperature and stirred for 3 h and
2
(CPs) and its Laplacian is expressed in terms of L(r) = –∇ (ρ(r))
quenched by the addition of saturated NH Cl solution. Then
and is calculated by using the Atoms In Molecule (AIM) theory
[39]. According to the topological properties, electron density is
4
the reaction mixture was extracted with DCM (3 × 10 ml).
2
2
The combined extracts were dried over Na SO , evaporation,
concentrated over ∇ (ρ(r))< 0 and is depleted for ∇ (ρ(r)) > 0.
2
4
2
Bardhan, Soumik
