J Chem Crystallogr (2012) 42:210–213
211
The solvents were removed in vacuo. The residue obtained
was added to a mixture of water (150 mL) and ethyl acetate
(100 mL) with stirring vigorously, and the ethyl acetate
layer was separated and dried over MgSO4. The residue
obtained upon evaporation of the ethyl acetate was
recrystallized from petroleum ether to give colorless crys-
tals of III (85%), The colorless single cryatals of the title
compound suitable for X-ray analysis were obtained by
slow evaporation of an n-hexane solution. m.p 71–73 ꢁC.
1H NMR (500 MHz, CDCl3) d7.15 (m, 2H), 7.24 (m, 3H),
6.57(s, 2H), 5.02(s, 1H), 4.22(q, 4H, J = 7.5 Hz), 3.47 (s,
2H), 1.30 (s, 18H), 1.23(t, 3H, J = 7.5 Hz). Anal. Calcd
for C28H28O5: C, 42.81; H, 5.03; Found: C, 42.68; H, 5.15.
CCl
4
HO
CH
3
+
NBS
HO
Benzoyl peroxide
Br
I
II
O
O
O
O
O
O
O
OH
O
LiNH
2
X-Ray Crystallography
III
Scheme 1 Route of synthesis of III
The data of single cryatals of the title compound III were
collected on a standard Rigaku Saturn 724 CCD Area
Detector System equipped with a normal-focus molybde-
recorded on a Bruker AVANCE II500 instrument in CDCl3
solution, using tetramethylsilane as an internal reference.
Elemental analyses were performed on a Perkin-Elmer
2400C instrument.
˚
num-target X-ray tube (k = 0.71073 A). The structure was
Table 1 Crystal data and structure refinement for III
Starting material 3,5-di-t-butyl-4-hydroxy toluene
I diethyl 2-phenylmalonates was commercially available
and used without further purification. All chemicals were
reagent grade and were used without further purification,
unless noted otherwise (Scheme 1).
Crystallographic data and structure refinement for complex 3
Empirical formula
Formula weight
Temperature (K)
C28 H38 O5
454.58
296(2)
˚
Wavelength (A)
0.71073
The Preparation of Substituted Benzyl Bromide II
Crystal system, space
group
Monoclinic, P21/c
˚
a = 9.8218(4) A, b = 13.5571(5) A,
˚
To a solution of I 3,5-di-t-butyl-4-hydroxy toluene (17.6 g,
0.08 mol) in 200 mL carbon tetrachloride1 was added
recrystallized N-bromosuccinimide (NBS, 15.8 g, 0.88
mol) and benzoyl peroxide (0.472 g, 0.002 mol). The
mixture was refluxed for 3.0 h at which time additional
NBS (1.4 g, 0.008 mol) and AIBN (0.24 g, 0.001 mol)
were added and the mixture refluxed for another 3 h. When
the reaction finished by TLC monitoring, heating was
stopped and the mixture was cooled at 0 ꢁC. The mixture
was filtered to remove succinimide and the filtrate was
concentrated under vacuum. The residue was redissolved in
ethyl acetate and washed with saturated solution of sodium
bicarbonate, brine, and then dried over MgSO4. Evapora-
tion of the solvent in vacuo afforded the crude benzyl
bromide compound II without purification (87.5%).
Unit cell dimensions
˚
c = 19.7233(8) A;
b = 102.3530(10)ꢁ
2565.46(18)
4, 1.177
3
˚
Volume (A )
Z, calculated density
(g cm-3
)
Absorption coefficient
(mm-1
F(000)
Crystal size (mm-3
0.079
)
984
)
0.41 9 0.24 9 0.03
1.84–31.11ꢁ
-13 B h B11, -13 B k B 18, -
27 Bl B 24
Range for data collection
Limiting indices
Reflections collected/
unique
17131/7093 [R(int) = 0.0253]
Completeness to
H = 31.11
85.8%
Synthesis of Substituent Diethyl Malonate (III)
Refinement method
Goodness-of-fit on F2
Full-matrix least-squares on F2
1.006
An anhydrous carbon tetrachloride solution (100 ml) of
3,5-di-t-butyl-4-hydroxy benzyl bromide 20.9 g (0.07 mol)
was added to an anhydrous carbon tetrachloride (150 ml)
of lithium amide (2.3 g, 0.1 mol) and diethyl phenylmal-
onate (16.1 g, 0.07 mol). The mixture was refluxed for 4 h.
Final R indices [I [ 2r(I)] R1 = 0.0507, wR2 = 0.1258
R indices (all data)
R1 = 0.0891, wR2 = 0.1484
Extinction coefficient
0.0045(8)
-3
˚
Largest diff. peak and hole 0.283 and 0.216 e A
123
Liu, Shou-Xin
