S.R. Nokhbeh, M. Gholizadeh, A. Salimi et al.
Journal of Molecular Structure 1242 (2021) 130718
134.23 and 135.58 (6 × s, C H ). FT-IR (KBr, ν¯ /cm 1): 539 (s), 689,
−
solvents. METTLER-TOLEDO DSC-822e thermal analyzer and Perkin
Elmer Diamond TG/DTA Instrument were used to record DSC and
TG/DTG/DTA thermograms, respectively. Perkin Elmer–Spectrum 65
FT-IR spectrometer was used to recording infrared spectra as a KBr
6
5
721 (s, C–H
bend.), 994 (w), 1112 (s, C-P stretch.), 1192 (w),
aromatic
1328 (w), 1437 (s, pH-P stretch.), 1484, 1585 (w, C–Haliphatic bend.),
2223 and 2291 (s, B-H stretch.), 2869, 2917 (w, C–Haliphatic stretch.),
3019, 3054 (w, C–Haromatic stretch.) (Figs. S1, S2, S3 and S4).
−
1
disk (4000 - 400 cm region).
3
.1. Preparation of 1,4-butanediylebis(triphenylphosphonium)
3
.5. General experimental procedure for reduction of aldehydes,
dibromide I
ketones and benzoyl chlorides to corresponding alcohols by III in
acetonitrile
6
.55 g Triphenyl phosphine (25 mmol, excess) was dissolved in
3
0 mL of DMF in a 50 mL flask and magnetically well stirred.
To the stirring solution of aldehyde (1 mmol) in CH CN (5 mL)
3
To this content, 1.01 mL of 1,4-dibromobutane (2.01 g, 10 mmol,
in a round-bottom flask (25 mL) the reducing agent III (1 mmol)
was added. The resulting mixture was stirred at room temper-
ature. Progress of the reaction was monitored by TLC (Eluent;
n-hexane/ethyl acetate: 10:3). After completion of the reaction,
3
d = 1.989 g/cm ) was added dropwise by an HPLC syringe. The
reaction mixture was refluxed for 4 h. After complete reaction,
the white precipitate was appeared. The reaction mixture was
cooled and the crude product was filtered and washed with DMF
CH OH (3 mL) was added to the mixture and stirred for an addi-
3
(
3 × 10 mL). Elemen. Anal. (%), Calcd.: C, 64.88; H, 5.13; Br, 21.60;
tional 1 h. The solvent was evaporated, and the crude product was
purified by chromatography on a silica gel plate (TLC silica gel 60 G
F254 25 glass plates 20 × 20 cm).
found: C, 64.62; H, 5.03; Br, 21.82 [70].
3
.2. Preparation of butane 4–bromo-1-(triphenyl phosphonium)
bromide (C22H23PBr ) II
2
3.6. General procedure for reduction of aldehydes, ketones and
benzoyl chlorides to related alcohols by III under the solvent-free
condition
To
a
solution of triphenyl phosphine (5.24 g, 20 mmol)
50 ml round–bottom flask equipped
in toluene (30 mL) in
a
with a magnetic stirrer and reflux condenser was added 1,4-
A
mixture of aldehyde (1 mmol) and reducing agent III
3
dibromobutane (3 mL, 30 mmol, d = 1.989 g/cm ) dropwise by a
(
1 mmol) was prepared and was well ground in a porcelain mortar
2
000 μL syringe. The reaction mixture was refluxed for 4 h. Af-
and pestle at room temperature. Progress of the reaction was mon-
itored by TLC (Eluent; n-hexane/ethyl acetate: 10:3). After comple-
ter complete reaction, the white precipitate was appeared. The
reaction mixture was cooled and the product was filtered and
washed with toluene (3 × 10 mL). The white powder was air-dried
overnight and recrystallized in water as needle shape crystals
tion of the reaction, CH OH (3 mL) was added to the mixture and
3
stirred for over 1 h. The solvent was evaporated, and the product
was purified by chromatography on a silica gel plate (60 G F254 25
glass plates).
(
5.57 g, 60% yield).). Elemen. Anal. (%), Calcd.: C, 55.23; H, 4.81; Br,
3
3.43; found: C, 55.20; H, 4.89; Br, 33.39.
The products were identified by comparison with their FT-IR,
mass, NMR spectra and physical data with those of authentic sam-
ples. The main products, reaction times and isolated yields are tab-
ulated in Tables 5, 6 and 7. For example, we have reported some
FT-IR, Mass, 1H and 13C NMR spectra of products as followed (see
supporting information file):
3
.3. Preparation of 1,3-propanediylbis(triphenylphosphonium)
bromide (C39H36P Br ) BC
2
2
An amount of triphenylphosphine (6.55 g, 25 mmol, excess)
was dissolved in DMF (30 mL) in a 50 mL flask and magnetically
−
well stirred. To this content, 1,3-dibromopropane (2.01 g, 1.01 mL,
4-chlorobenzyl alcohol: FT-IR (KBr, ν¯ /cm 1): 798 (m), 836 (m),
1011, 1027 (s), 1491 (s), 3264, 3350 (broad, s). Mass Spec-
trum: m/z (intensity,%) = 143 (18), 141 (69), 124 (13), 113
(16), 107 (98), 77 (100), 51 (23), 29(47). 1H NMR (300 MHz,
3
10 mmol, d = 1.989 g/cm ) was added dropwise by an HPLC syringe.
The reaction mixture was refluxed for 3.5 to 4 h. After complete
reaction, the white precipitate was appeared. The reaction mixture
was cooled and the crude product was filtered and washed with
DMF (3 × 10 mL). The fine powder was dried overnight and recrys-
tallized in water (6.9 g, 95% yield), m.p. 349–353 °C (by DSC and
DTA) [51].
CDCl , δ; ppm): 2.21, 2.23, 2.50 (t, 3JH
= 4.8, OH), 4.65,
= 8.4, CHaromatic,
3
–
H
4.66 (d, 3JH
= 4.8, 2H), 7.28, 7.31 (d, 3JH
–
H
–
H
3
13
2H), 7.34, 7.36 (d,
J
–
= 8.4, CH
, 2H).
aromatic
C NMR
H
H
(75 MHz, CDCl , δ; ppm): 64.43 (CH ), 128.68, 128.29,
3
2
1
33.35, 139.26 (4 × s, C H ).
6
5
−
3
.4. Preparation of 1,3-propanediylbis(triphenylphosphonium)
tetrahydroborate (C39H36P B H ) III
4-methoxybenzyl alcohol: FT-IR (KBr, ν¯ /cm 1): 816 (m), 1033
(m), 1248, 1513, 1612 (s), 3355 (broad, s).
2
2
8
4
-methylbenzyl alcohol: FT-IR (KBr, ν¯ /cm 1):803 (s), 1014, 1030
(s), 1445, 1517 (m), 3284, 3356 (broad, s). Mass Spectrum:
m/z (intensity,%) = 122 (98), 107 (100), 93 (88), 79 (92), 65
−
An amount of compound BC, 2.38 g, (20 mmol) was dissolved
in H O (30 mL) in 70 °C in a 50 mL beaker. To this content, an
2
aqueous solution of sodium borohydride (2.06 g, 40 mmol in 50 mL
water at pH = 14, adjusted with NaOH pellets) was added drop-
wise with continuous magnetically stirring for 30 min. The solu-
tion was mixed for over 20 min. The white precipitate was fil-
tered and washed with cooled water (3 × 10 mL). The product was
air-dried overnight (97% yield), Decomposition point 340 °C (by
(67), 51 (56), 39 (68). 1H NMR (300 MHz, CDCl , δ; ppm):
1.76 (s, OH), 2.39 (s, CH , 3H), 4.67, 4.68 (d, 3JH
3
= 3.3,
3
–
H
CH , 2H), 7.20, 7.22 (d, 3JH
= 7.8, CH
, 2H), 7.28, 7.31
aromatic
2
–
H
(d, 3JH
= 7.8, CHaromatic, 2H). C NMR (75 MHz, CDCl , δ;
13
–
H
3
ppm,): 21.17 (CH ), 65.29 (CH ), 127.15, 129.27, 137.42, 137.94
3
2
(4 × s, C H ).
6
5
DSC and DTA). 1H NMR (300 MHz, DMSO–d , δ; ppm): 1.8 (p,
4-nitrobenzyl alcohol: Mass Spectrum: m/z (intensity,%) = 153
(82), 135 (81), 123 (33), 107 (92), 89 (86), 77 (100), 63 (47),
51 (82), 39 (38) and 29 (53). 1H NMR (300 MHz, CDCl3,
6
3JH
= 8.1, 2H), 4 (t, 3JH
= 12.6, 4H), 7.76–7.91(m, 30H, 6 × C H ),
–
H
–
H
6
5
1
11
−
0
.27, 0.00, −0.26 and −0.53 (4 × s,
J
= 81.3 for BH ), 0.14,
1
1B- H
4
1
0
.05, −0.03, −0.12, −0.22, −0.31 and −0.40. (7 × s,
J
= 27.3 for
δ; ppm): 2.40 (s, OH), 4.86 (s, CH , 2H), 7.54, and 7.57
10B-H
2
10
−
31
(d, 3JH
= 8.7, CHaromatic, 2H), 8.22 and 8.24 (d, 3JH
BH ). P NMR (200 MHz, DMSO–d , δ; ppm): one strong peak
–
–
H
= 8.7,
4
6
H
at 34.748 ppm for P atom. 13C NMR (75 MHz, DMSO–d6, δ; ppm):
CHaromatic, 2H). C NMR (75 MHz, CDCl , δ; ppm,): 64.01
13
3
16.59(s, C20), 21.03 (s, C21, C19), 117.70, 118.86, 128.81, 130.78,
(CH ), 123.76, 127.10, 128.64, 132.06 (4 × s, C H ).
2
6
5
10