2132 J. Am. Chem. Soc., Vol. 119, No. 9, 1997
Burns et al.
para-toluenesulfonyl chloride, and methanesulfonyl chloride were used
as received from Aldrich. GC standard decane, docedcane, tridecane,
eicosane, hexylbenzene, heptylbenzene, and propylbenzene were used
as received from Aldrich. GC standard 1,3-bis(2-methoxyphenyl)-
propane was prepared by a previously reported method.5 Allylmag-
nesium chloride and vinylmagnesium bromide were purchased from
Aldrich and assayed by literature procedure.23
(t, 3H, J ) 7.5 Hz), 1.25 (d, 3H, J ) 6.3 Hz), 1.52-1.67 (m, 2H),
2.45 (s, 3H), 4.51-4.50 (m, 1H), 7.32 (d, 2H, J ) 8.1 Hz), 7.79 (d,
2H, J ) 8.3 Hz).
4-Methylbenzenesulfonic Acid, Cyclopentyl Ester (38). Prepared
1
as a clear solid in 91% yield: mp 26 °C (lit.26 28 °C); H NMR δ
1.50-1.60 (m, 2H), 1.66-1.85 (m, 6H), 2.45 (s, 3H), 4.92-5.00 (m,
1H), 7.34 (d, 2H, J ) 8.1 Hz), 7.79 (d, 2H, J ) 8.4 Hz).
All melting points (Mel-Temp) and boiling points (micro boiling
point apparatus) are uncorrected. 1H NMR spectra were recorded at
300 MHz in CDCl3 with Me4Si as an internal standard unless otherwise
specified. Silica gel (Davisil 633) was used for column chromatog-
raphy, and analytical thin layer chromatography was performed using
precoated Analtech Uniplates (silica gel GF). Samples that underwent
spectral and analytical analysis were purified by radial chromatography
using a Chromatotron. Elemental analysis was done by Desert
Analytics, Tucson, AZ. Gas chromatographs (GC) were obtained with
a Hewlett Packard Series II 5890 GC, utilizing a J&W capillary column
(DB5, 30 m) and FID detection, and chromatogram signals were
integrated using Water’s Baseline 810 software. Identities of known
compounds in product mixtures were obtained either from GC by
comparison with an authentic standard and/or GC/MS. An internal
standard method24 was used to determine yields by GC; standards used
were dodecane, tridecane, heptylbenzene, propylbenzene, and 1,4-bis-
(2-methoxyphenyl)butane,25 depending on the nature of the product
mixtures. GC/MS were obtained with a Varian 3400 GC (SGE capillary
column, BP1, 30 m) interfaced to a Finnigan Incos 50 mass spectrom-
eter. All reactions were run under a nitrogen atmosphere obtained by
passing the nitrogen through a drying tower containing 3 Å molecular
sieves.
6-[(4-Methylbenzenesulfonyl)oxy]hexanoic acid, ethyl ester (41).
Prepared as a clear oil in 84% yield: bp 246-247 °C. IR (cm-1) 2932
, 2355, 1732, 1595, 1355, 1259, 1173, 1033, 1029, 949, 815; 1H NMR
δ 1.25 (t, 3H, J ) 7.28 Hz), 1.31-1.39 (m, 2H), 1.55-1.60 (m, 2H),
1.64-1.69 (m, 2H), 2.23-2.28 (t, 2H, J ) 7.6 Hz), 2.45 (s, 3H), 4.00-
4.04 (t, 2H, J ) 6.4 Hz), 4.08-4.15 (q, 2H, J ) 7.22 Hz), 7.33-7.36
(d, 2H, J ) 8.74), 7.78-7.80 (d, 2H, J ) 8.36 Hz); 13C NMR (75.4
MHz, CDCl3) δ 173.2, 144.6, 133.1, 129.7, 127.7, 77.4, 77.0, 76.6,
70.2, 60.1, 33.9, 33.8, 28.4, 28.3, 24.8, 24.7, 24.1, 21.5, 14.1; LRMS
m/z 314 (M+), 269, 155, 143, 91. Anal. Calcd for C15H22O5S: C,
57.31; H, 7.05. Found: C, 57.14; H, 7.14.
Procedure for the Preparation of Mesylates. A stirred solution
of CH2Cl2 (240 mL), 2-butanol (6.02 g, 81 mmol), and triethylamine
(12.33 g, 121.8 mmol) was cooled on an ice bath, and methanesulfonyl
chloride (10.2 g, 89.3 mmol) was added via syringe at a rate of 0.23
mL/min. The reaction was allowed to stir for 1 h at this temperature
and then quenched with 250 mL of ice-water. The mixture was
washed successively with 1.5 M HCl (200 mL), 10% NaHCO3 (200
mL), and brine (200 mL). The organic layer was dried over Na2SO4
and concentrated under vacuum. The crude product was purified by
silica gel chromatography (CH2Cl2) and dried over P2O5 in a vacuum
desiccator for 24 h, furnishing 11.59 g (94%) of methanesulfonic acid,
sec-butyl ester (37) as a clear oil: bp 235 °C (lit.30 61 °C, 0.5 Torr);
1H NMR δ 0.99 (t, 3H, J ) 7.5 Hz), 1.41 (d, 3H, J ) 6.3 Hz), 1.62-
1.80 (m, 2H), 3.01 (s, 3H), 4.72-4.80 (m, 1H).
Procedure for the Preparation of Tosylates. p-Toluenesulfonyl
chloride (6.7 g, 87.6 mmol) was added over a period of 30 min to a
stirred solution of pyridine (27.7 g, 350 mmol) and n-propanol (6.32
g, 105 mmol) maintained at 0 °C (1.0 equiv of alcohol was used in the
syntheses of the tosylates except for tosylates 10 and 32, where 1.2
equiv of alcohol were used). The reaction mixture was allowed to stir
an additional 3 h (6 h for secondary tosylates) and then quenched with
Methanesulfonic Acid, Cyclopentyl Ester (40). Prepared as a clear
1
oil in 91% yield: bp 232 °C (lit.31 71 °C, 1 Torr); H NMR δ 1.62-
1.70 (m, 2H), 1.75-1.85 (m, 2H), 1.90-2.01 (m, 4H), 3.00 (s, 3H),
5.15-5.19 (m, 1H).
H2O (150 mL) and extracted with CH2Cl2 (3
combined organic layers were washed with 3 M HCl (3
60 mL), and the
80 mL)
Synthesis of Catalyst A: Li2CuCl4. Lithium chloride (0.0963 g,
1.29 mmol) and copper(II) chloride (0.1525 g, 1.29 mmol) were
weighed into a 25 mL flask under nitrogen in a glovebag or a drybox.
The flask was removed from the bag or box and cooled on an ice bath,
and dry THF (11.40 mL) was then added. The mixture was allowed
to stir for approximately 5 min or until all species were soluble in the
resulting 0.1 M bright orange-red solution.
Synthesis of Catalyst C: Li2CuBr2SMe2SPh. Lithium bromide
(0.112 g, 1.29 mmol), lithium thiophenolate (0.150 g, 1.29 mmol), and
copper(I) bromide dimethyl sulfide (0.266 g, 1.29 mmol) were weighed
into a 50 mL flask in a glovebag or drybox under nitrogen. The flask
was removed from the bag or box, placed in an ice bath to cool, and
then THF (12.90 mL) was added. The mixture was allowed to stir
until all species were soluble in the resulting 0.1 M clear yellow
solution. The catalyst was kept in an ice bath and used within the first
2-3 h of its preparation: 1H NMR (THF-d8) δ 2.04 (s, 6H), 6.65-
6.83 (m, 3H), 7.30-7.52 (m, 2H); UV/visible (THF) λmax nm (ꢀ) 216
(4.38 105), 266 (2.49 105).
followed by 10% NaHCO3 (1 80 mL). The organic layer was dried
over Na2SO4 and concentrated under vacuum and the crude product
purified by silica gel chromatography (CH2Cl2). Azeotrope distillation
with benzene (tosylates 21, 35, and 38 were dried in a vacuum
desiccator over P2O5) yielded 18.0 g (96%) of 4-methylbenzenesulfonic
acid, propyl ester (10) as a clear oil: bp 153 °C (lit.26 154-156°); 1H
NMR δ 0.90 (t, 3H, J ) 7.3 Hz), 1.62-1.73 (m, 2H), 2.45 (s, 3H),
3.99 (t, 2H, J ) 7.2 Hz), 7.36 (d, 2H, J ) 8.3 Hz), 7.90 (d, 2H, J )
8.3 Hz).
4-Methylbenzenesulfonic Acid, Heptyl Ester (11). Prepared as a
1
clear oil in 88% yield: bp 201 °C (dec) (lit.27 92 °C, 3 mmHg); H
NMR δ 0.86 (t, 3H, J ) 6.6 Hz), 1.18-1.35 (m, 10H), 1.59-1.69 (m,
2H), 2.45 (s, 3H), 4.02 (t, 2H, J ) 6.6 Hz), 7.35 (d, 2H, J ) 8.1 Hz),
7.79 (d, 2H, J ) 8.4 Hz).
4-Methylbenzenesulfonic Acid, Dodecyl Ester (21). Prepared as
a clear solid in 88% yield: mp 30 °C (lit.28 30 °C); 1H NMR δ 0.857-
0.903 (m, 3H), 1.18-1.35 (m, 18H), 1.59-1.68 (m, 2H), 2.45 (s, 3H),
4.02 (t, 2H, J ) 6.6 Hz), 7.34 (d, 2H, J ) 8.1 Hz), 7.79 (d, 2H, J )
8.4 Hz).
Lithium Thiophenolate (LiSPh). Thiophenol (4.00 g, 36.30 mmol)
was added to Et2O (42 mL) in a 100 mL Schlenk flask attached to a
double-ended filter funnel, and the mixture was cooled with an ice
bath. Methyllithium (39.93 mmol in 30.7 mL of Et2O) was added at
a rate of 1.02 mL/min to the flask. The reaction was stirred overnight,
gradually warming to room temperature. After 24 h, the apparatus
was turned upside-down and the reaction mixture was vacuum filtered
4-Methylbenzenesulfonic Acid, Isopropyl Ester (32). Prepared
1
as a clear oil in 94% yield: bp 129 °C (dec) (lit.26 mp 20 °C); H
NMR δ 1.27 (d, 6H, J ) 6.6 Hz), 2.45 (s, 3H), 4.69-4.77 (m, 1H),
7.34 (d, 2H, J ) 7.8 Hz), 7.79 (d, 2H, J ) 8.7 Hz).
and the remaining white salt washed with Et2O (2
35 mL). The
4-Methylbenzenesulfonic Acid, sec-Butyl Ester (35). Prepared as
a clear oil in 99% yield: bp 109 °C (dec) (lit.29 dec); 1H NMR δ 0.815
powdery white salt was dried under strong vacuum to remove any trace
of solvent, yielding 4.11 g (98%) of lithiated thiophenol: 1H NMR δ
(THF-d8) δ 6.49-6.55 (m, 1H), 6.70 (t, 2H, J ) 7.5 Hz), 7.25 (d, 2H,
(23) Watson, S. C.; Eastham, J. F. J. Organomet. Chem. 1967, 9, 165-
168.
(24) (a) Grant, D. W. Capillary Gas Chromatography; John Wiley and
Sons, Inc.: New York, 1996; pp 235-252. (b) Schomburg, G. Gas
Chromatography; VCH Publishers, Inc: New York, 1990; pp 108-122.
(25) Unpublished work; this compound gave satisfactory spectral and
elemental analysis.
J ) 7.4 Hz); UV/visible (THF) λmax nm (ꢀ) 218 (9.14
102), 292
(1.66 103).
Typical Procedure and Variations Used in the Copper-Catalyzed
Substitution Reaction. Tridecane (13). 1-Bromodecane (0.70 g, 3.17
mmol) in 3.4 mL of THF was added at a rate of 0.33 mL/min to Mg
(26) Drahowzal, F.; Klamman, D. Monatsh. Chem. 1951, 82, 452-459.
(27) Carman, R. M.; Kibby, J. J. Aust. J. Chem. 1976, 26, 1761-1767.
(28) Sekera, V. C.; Manel, C. S. J. Am. Chem. Soc. 1933, 55, 345-349.
(29) Gilman, H.; Beaber, N. J. J. Am. Chem. Soc. 1925, 47, 518-525.
(30) Helmkamp, R. J. Org. Chem. 1957, 22, 479-481.
(31) Mosher, H. S.; Williams, H. R. J. Am. Chem. Soc. 1954, 76, 2987-
2990.