Synthesis of optically pure 3,3′-diaryl binaphthyl disulfonic acids via stepwise N-S bond cleavage

Article abstract of DOI:10.1021/jo401848z

We developed a practical synthesis of optically pure 3,3′-diaryl-1, 1′-binaphthyl-2,2′-disulfonic acids (i.e., (R)- or (S)-3,3′-Ar₂-BINSAs) from the parent chiral sulfonimides via stepwise N-S bond cleavage of the sulfonimides and the resultant sulfonamides. This unusual synthesis, which provides arylsulfonic acids from arylsulfonamides, is valuable since common methods particularly give amines with the decomposition of sulfone groups during deprotection.

Full text of DOI:10.1021/jo401848z

Article
pubs.acs.org/joc
Synthesis of Optically Pure 3,3′-Diaryl Binaphthyl Disulfonic Acids via
Stepwise N−S Bond Cleavage
†
†
†
,†,‡
Manabu Hatano, Takuya Ozaki, Keisuke Nishikawa, and Kazuaki Ishihara*
†
‡
Graduate School of Engineering, Nagoya University, and Japan Science and Technology Agency (JST), CREST, Nagoya University,
Furo-cho, Chikusa, Nagoya 464-8603, Japan
*
S Supporting Information
ABSTRACT: We developed a practical synthesis of optically
pure 3,3′-diaryl-1,1′-binaphthyl-2,2′-disulfonic acids (i.e., (R)-
or (S)-3,3′-Ar -BINSAs) from the parent chiral sulfonimides
2
via stepwise N−S bond cleavage of the sulfonimides and the
resultant sulfonamides. This unusual synthesis, which provides
arylsulfonic acids from arylsulfonamides, is valuable since
common methods particularly give amines with the decom-
position of sulfone groups during deprotection.
INTRODUCTION
In general, arylsulfonic acids have been used to protect amino
functions due to the high stability of the corresponding
arylsulfonamides. Inevitably, for cleavage of the protecting
■
Among a variety of recent powerful and environmentally
benign organocatalysts, many researchers have become
interested in chiral Brønsted acid catalysts. In particular, strong
7
sulfone group from the amino group, drastic reaction
conditions are usually needed, including the use of strong
1
Brønsted acid catalysts such as phosphoric acids, N-triflyl
8
9
10
11
acids, strong bases, SmI , TiCl3, Bu SnH/2,2′-azodiiso-
2
3
4
2
3
phosphoramide, disulfonic acids, and sulfonimides with a
12
13
butyronitrile (AIBN), Li and Mg powder, Na/naphtha-
5
chiral 3,3′-disubstituted binaphthyl backbone are highly
attractive since their simple C -symmetric structures are useful
for the design of a variety of reactions. However, the
14
15
16
lene, photolysis, and electrolysis. Most importantly, these
methods have been developed for amines, but not for sulfonic
acids, and we can obtain deprotected amines selectively, while
sulfonic acids would usually decompose and be discarded. As a
good example, Fukuyama and Kan’s nitrobenzenesulfonamide
2
introduction of 3,3′-disubstituents has not been well established
3
for chiral 1,1′-binaphthyl-2,2′-disulfonic acid (BINSA), due to
synthetic difficulties, unlike for chiral binaphthyl phosphoric
(Ns) can provide the desired amines even under mild basic
1
17
acid. In particular, the key to synthesizing chiral 3,3′-Ar -
conditions with thiolates (Scheme 2).
However, an
2
BINSAs (1) from chiral BINOL (1,1′-bi-2-naphthol) should be
Suzuki−Miyaura coupling, Newman−Kwart rearrangement,
and oxidation (Scheme 1). Only one successful example has
arylsulfone moiety would decompose with the release of SO2
via the Meisenheimer complex.
4
a
been reported by List, who synthesized (R)-3,3′-[3,5-
RESULTS AND DISCUSSION
■
(
CF ) C H ] -BINSA, since the Newman−Kwart rearrange-
3
2
6
3 2
Cleavage of the N−S Bond of Sulfonimide (R)-2a. We
ment (95% yield) and subsequent oxidation (81% yield) are
facilitated by taking advantage of electron-withdrawing
initially examined the N−S cleavage of (R)-3,3′-Ph -1,1′-
2
4c
binaphthyl-2,2′-sulfonimide ((R)-2a) as a probe compound
6
substituents at the 3,3′-positions (Scheme 1, route a). In this
(
Scheme 3). However, (R)-2a was perfectly intact under strong
regard, we have reported the synthesis of (R)-3,3′-Ph -BINSA
2
acidic (8 M HCl aq.) or strong basic (2 M NaOH/MeOH)
(
(R)-1a) in the same way, but the yield was low in the
conditions, since NH is a poor leaving group. In particular, the
3
3f
rearrangement (25%) and oxidation (30%). Moreover, we
also reported the second synthetic route, which employed
Suzuki−Miyaura coupling in the last step, but the yield was low
deprotonation of sulfonimide under basic conditions might
strengthen the N−S bond due to the conjugated structure.
Therefore, we decided to replace the active proton with a
methyl group using the Meerwein reagent (Me O·BF ).
3f
(
<10%) (Scheme 1, route b). As the third synthetic route to
3
4
chiral 3,3′-Ar -BINSAs, the deprotection of 3,3′-diaryl-1,1′-
Compound (R)-2a was transformed to a N-Me compound
((R)-3a), and we could cleave the first N−S bond of
sulfonimide (R)-3a with the use of 2 M NaOH in MeOH at
reflux temperature, to give (R)-4a in quantitative yield.
Compound (R)-4a still has an active proton, and we protected
2
binaphthyl-2,2′-sulfonimides ((R)-2) may be possible (Scheme
1
, route c). Remarkably, Lee recently developed a practical
synthesis of (R)-2 from the parent (R)-3,3′-dibromo
4c
compound by Suzuki−Miyaura coupling with ArB(OH) .
2
Therefore, in this paper, we envisioned that chiral 3,3′-Ar -
2
BINSAs (1) could be obtained efficiently if we cleaved the two
stable N−S bonds in 2.
Received: August 20, 2013
Published: September 26, 2013
©
2013 American Chemical Society
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Article
Scheme 1. Synthesis of (R)-3,3′-Ar -BINSAs
2
Scheme 2. Deprotection of Nitrobenzenesulfonamide (Ns
Amide) with the Release of SO2
to this report, we examined the reaction of (R)-6a with KPPh2,
but the desired arylsulfinic acid (R)-9a was not obtained
(
Scheme 4, eq 2).
As another promising method, the nucleophilic substitution
of trialkylaminosulfonates with N−S cleavage has been
20
reported. We investigated the reaction of model compound
0 with MeOTf and subsequent workup with water (Scheme 5,
1
the SO Na moiety with Et O·BF ((R)-5a, 98% yield) and the
eq 3). As a result, the desired 11 was obtained in 55% yield.
Encouraged by this preliminary result, we next examined the
reaction of (R)-6a under the same conditions. However, since
(R)-6a was much less reactive than 10, arylsulfone (R)-12,
instead of the desired product, was obtained by an intra-
3
3
4
SO NHMe moiety with Me O·BF ((R)-6a, 85% yield).
2
3
4
Noteworthy is that SO Et is much more stable than SO Me,
3
3
which would be easily hydrolyzed to SO H and recyclized even
3
by silica gel chromatography.
21
Trials for Cleavage of the N−S Bond of Sulfonamide
molecular Friedel−Crafts reaction (Scheme 5, eq 4).
(
R)-6a. We next examined cleavage of the N−S bond in
Sulfonamide to Sulfonic Acid via Stepwise Reduction
and Oxidation. Finally, we examined reductive cleavage of the
N−S bond of sulfonamides with aluminum hydride reagents,
sulfonamide (R)-6a. However, treatment of (R)-6a with either
an acid or base was again ineffective (Scheme 4, eq 1). The
22
desired (R)-3,3′-Ph -BINSA salts were not obtained, and the
which has scarcely been developed since the products would
be a mixture of unstable sulfinic acids, sulfenic acids, thiols, and
disulfides. However, we expected that the desired sulfonic acids
could be convergently obtained if we treated the mixture
2
sulfonamide moieties in recovered (R)-7a and (R)-8a were
intact. Very recently, Tomooka reported a nucleophilic
substitution reaction at the nitrogen of arylsulfonamides with
3c
a phosphide anion such as KPPh to provide phosphamides, in
without purification with suitable strong oxidants. Under this
2
18
19
addition to unstable arylsulfinic acid (ArSO H). According
assumption, we conducted the stepwise reduction and
2
Scheme 3. Cleavage of the N−S Bond of Sulfonimide (R)-2a
1
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Scheme 4. Trials for Cleavage of the N−S Bond of (R)-6a
Scheme 5. Nucleophilic Substitution of Trialkylaminosulfonates
Table 1. Transformation of Sulfonamide to Sulfonic Acid via Stepwise Reduction and Oxidation
a
b
entry
reduction conditions
oxidation conditions
yield (%) of 14
a
1
DIBAL (10 equiv), THF, 40 °C, 22 h
O (5 atm), KOH, HMPA, 80 °C, 10 h
2
0
c
2
3
4
LiAlH (10 equiv), THF, 40 °C, 22 h
Red-Al (10 equiv), THF, 40 °C, 22 h
Red-Al (5 equiv), THF, rt, 5 h
O (5 atm), KOH, HMPA, 80 °C, 10 h
46 (ca. 30)
4
2
c
O (5 atm), KOH, HMPA, 80 °C, 10 h
71 (ca. 5)
2
O (balloon), DMF, 60 °C, 16 h
2
97
a
b
c
DIBAL = i-Bu AlH, Red-Al = NaAlH (OC H OCH ) . HMPA = hexamethylphosphoramide, DMF = N,N-dimethylformamide. Yield (%) of
2
2
2
4
3 2
naphthalene.
oxidation for 13 as a preliminary investigation (Table 1).
eq 5). Moreover, we found that the oxidation of 15 can readily
LiAlH (10 equiv) gave the desired product 14 in 46% yield in
proceed (up to 97% yield) with or without KOH in HMPA or
4
two steps, while i-Bu AlH (DIBAL) showed low reactivity
DMF under O (balloon) conditions (Scheme 6, eq 6), while
2
2
(
entries 1 and 2). Moreover, a significant amount of
the oxidation of 16 was sluggish (64% yield) even if KOH was
naphthalene was obtained due to overreaction with reactive
used under O (balloon) (Scheme 6, eq 7). This result means
2
2
3
LiAlH4. In place of LiAlH , when we used less reactive
that the selective reduction of sulfonamide to sulfinic acid is
important for stepwise reduction and oxidation to synthesize
sulfonic acid from sulfonamide. Ultimately, the yield of 14 was
improved up to 97% (Table 1, entry 4), when we used Red-Al
4
24
NaAlH (OC H OCH ) (Red-Al, 10 equiv), 14 was obtained
2
2
4
3 2
in 71% yield (entry 3). In entry 3, more than three spots were
observed in TLC analysis after the reduction step.
To investigate the major compounds which were obtained in
entry 3 in Table 1, we conducted the reduction step by using
Red-Al (10 equiv) in THF at 40 °C (Scheme 6, eq 5). After the
workup and purification, a major product was identified as 2-
naphthyl disulfide (16) (70% yield). In sharp contrast, we could
isolate 2-naphthalenesulfinic acid (15) in 95% yield when we
used Red-Al (5 equiv) in THF at room temperature (Scheme 6,
(5 equiv) and then O (balloon) without KOH in DMF in
place of HMPA without purification after the reduction.
2
Synthesis of (R)-3,3′-Ph -BINSA from (R)-6a. With this
2
optimized method in hand, we transformed sulfonamide (R)-6a
to the disulfonates (R)-17a, where both the SO NMe and
2
2
SO Et moieties might be reduced and oxidized (Scheme 7, eq
3
8). As a result, (R)-17a was obtained in 39% yield in two steps
1
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Scheme 6. Reduction of Sulfonamide and Oxidation of Sulfinic Acid and Disulfide
Scheme 7. Synthesis of (R)-3,3′-Ph -BINSA ((R)-1a)
that (S)-compounds with phenyl, 4-biphenyl, and 3,5-terphenyl
substituents could be synthesized smoothly without serious
problems, as shown in Scheme 8. The total yield of (S)-1a−c in
nine steps from (S)-20 was 33%, 46%, and 46%, respectively.
Later, we could develop the improved method by double N,O-
methylation of (S)-4b with the use of Me O·BF and hydrolysis
2
3
4
to give (S)-8b, which would be transformed to (S)-17b via
reduction and oxidation (Scheme 9). Therefore, we can
synthesize chiral 3,3′-Ar -BINSAs from the known compound
2
20 in eight steps.
CONCLUSIONS
■
In summary, we have developed a practical synthesis of
optically pure 3,3′-Ar -BINSAs from the parent sulfonimides
2
via stepwise N−S bond cleavage of the sulfonimides and the
resultant sulfonamides. (R)- or (S)-3,3′-Ar -BINSAs would be
2
highly attractive as chiral organocatalysts and chiral bidentate
ligands. Moreover, basically, this synthesis should be valuable as
a general method for obtaining arylsulfonic acids from
arylsulfonamides.
EXPERIMENTAL SECTION
■
with 3,3′-diphenyl-1,1′-binaphthalene (18) (<5% yield). This
moderate yield was due to the over-reduction of the more
reactive SO Et moiety compared to the SO NMe moiety, and
it was difficult to oxidize these over-reduction intermediates
under the mild reaction conditions without KOH. Therefore, to
avoid the over-reduction, (R)-6a was hydrolyzed in advance to
sulfonate (R)-8a, and then we tried the reduction/oxidation
procedure. As a result, the yield of (R)-17a was improved to
General Information. Reactions were performed under nitrogen
unless otherwise noted. Reagents were purchased from commercial
suppliers and used without purification unless otherwise noted.
Solvents such as dichloromethane, 1,2-dichloroethane, methanol, and
THF were distilled prior to use. NMR spectra were measured on a 400
3
2
2
1
13
MHz spectrometer for H NMR and a 100 MHz spectrometer for
C
NMR. High resolution mass spectral analyses (HRMS) were
performed by FAB, EI, and ESI techniques. High performance liquid
chromatography (HPLC) analysis was conducted with a chiral column
6
8% (Scheme 7, eq 9). Subsequent protonation by ion
(
250 mm). Column chromatography was performed using silica gel
(100−210 mesh).
R)-N-Methyl-3,3′-diphenyl-1,1′-binaphthyl-2,2′-sulfonimide
exchange ultimately provided the desired (R)-3,3′-Ph -BINSA
2
(
1a) without a loss of optical purity (>99% ee), which was
determined by HPLC analysis of diethyl ester (R)-19a and (S)-
9a from (R)-1a and (S)-1a, respectively. Not surprisingly, the
reduction/oxidation procedure was not effective for (R)-2a,
R)-3a, (R)-4a, or (R)-5a, and a complex mixture was obtained
(
4c
((R)-3a). A well dried Schlenk flask was charged with (R)-2a (328.6
mg, 0.60 mmol) and K CO (249 mg, 1.80 mmol) under a nitrogen
1
2
3
atmosphere. Dichloromethane (10 mL) was added, and the
suspension was cooled to 0 °C. Trimethyloxonium tetrafluoroborate
266.2 mg, 1.80 mmol) was added, and the mixture was warmed to
room temperature for 4 h by monitoring with TLC. Then a saturated
NH Cl aqueous solution (5 mL) was poured into the reaction mixture,
and the product was extracted with ethyl acetate (15 mL × 2). The
combined extracts were washed with brine (10 mL) and dried over
(
(
with the generation of 18.
Synthesis of (S)-3,3′-Ar -BINSAs from (S)-20. This
2
4
methodology was effective for the synthesis of bulky (R)- and
(
2
2
S)-3,3′-Ar -BINSAs (1). We could use N-Me sulfonimide (S)-
2
1 as a common intermediate after the N-methylation of (S)-
MgSO . The organic phase was concentrated under a reduced
4
4
c
0
in the initial step (Scheme 8). Overall, we demonstrated
pressure, and the crude product was purified by silica gel column
1
0408
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Scheme 8. Synthesis of (S)-3,3′-Ar -BINSAs ((S)-1a−c) (a: Ar = Ph, b: Ar = 4-biphenyl, c: Ar = 3,5-terphenyl)
2
Scheme 9. Improved Method by Double N,O-Methylation of
S)-4b and Hydrolysis
NMR (400 MHz, CD OD) δ 2.30 (s, 3H), 6.96 (d, J = 8.7 Hz, 1H),
3
7
7
1
.16−7.38 (m, 6H), 7.39−7.48 (m, 4H), 7.51 (t, J = 7.3 Hz, 1H),
(
.57−7.69 (m, 4H), 7.76 (s, 1H), 7.80 (s, 1H), 7.85 (d, J = 9.1 Hz,
H), 7.87 (d, J = 8.2 Hz, 1H). 13C NMR (100 MHz, CD OD) Many
3
peaks overlapped. δ 28.9, 127.3, 127.4, 127.7, 127.9, 128.2, 128.4,
1
1
28.5, 128.6, 129.4, 130.9, 131.2, 131.3, 132.8, 134.0, 134.5, 134.7,
35.4, 136.1, 138.7, 140.3, 140.4, 142.4, 142.7, 144.6. Mp 273 °C
−1
23
D
(decomposed). IR (KBr) 3376, 1494, 1326, 1170, 1041 cm . [α]
=
1
55 (c 1.0, CH OH, (R)). HRMS (FAB+, Magnetic sector) calcd for
3
+
C H NNa O S [M + Na] 624.0891, found 624.0899.
33
24
2
5 2
(
R)-Ethyl 2′-(N-Methylsulfamoyl)-3,3′-diphenyl-(1,1′-bi-
naphthyl)-2-sulfonate ((R)-5a). A well dried Schlenk flask was
chromatography (eluent: hexane/EtOAc = 3:1), to give the desired
product ((R)-3a) (337.0 mg, >99% yield). 1H NMR (400 MHz,
charged with (R)-4a (120.3 mg, 0.20 mmol) and K
CO (69.1 mg,
2
3
0
.50 mmol) under a nitrogen atmosphere. Dichloromethane (7.5 mL)
CDCl ) δ 2.95 (s, 3H), 7.25 (d, J = 8.2 Hz, 2H), 7.39−7.48 (m, 12H),
3
13
was added, and the suspension was cooled to 0 °C. Then a 1.0 M
7
.68 (t, J = 7.3 Hz, 2H), 7.98 (d, J = 8.2 Hz, 2H), 8.06 (s, 2H). C
CH Cl solution of triethyloxonium tetrafluoroborate (0.50 mL, 0.50
2
2
NMR (100 MHz, CDCl ) δ 30.7, 127.3 (2C), 127.8 (2C), 127.9 (2C),
3
mmol) was added, and the mixture was warmed to room temperature
for 20 h by monitoring with TLC. Then 5 mL of saturated NH Cl
aqueous solution were poured into the reaction mixture, and the
product was extracted with ethyl acetate (15 mL × 2). The combined
extracts were washed with brine (10 mL) and dried over MgSO . The
organic phase was concentrated under reduced pressure, and the crude
product was purified by silica gel column chromatography (eluent:
1
28.3 (2C), 128.4 (2C), 128.5 (2C), 128.7 (2C), 130.0 (2C), 130.4
4
(
2C), 131.8 (2C), 132.2 (2C), 133.8 (2C), 134.5 (2C), 138.0 (2C),
1
2
39.0 (2C), 139.8 (2C). Mp 278 °C (decomposed). IR (KBr) 3056,
1 24
−
932, 1366, 1349, 1176, 1029 cm . [α] = 38.8 (c 1.0, CHCl , (R)).
D
3
+
4
HRMS (FAB+, Magnetic sector) calcd for C H NO S [M + H]
33
24
4 2
5
62.1147, found 562.1150.
Sodium (R)-2′-(N-Methylsulfamoyl)-3,3′-diphenyl-(1,1′-bi-
naphthyl)-2-sulfonate ((R)-4a). To a solution of NaOH (8.0 g,
00 mmol) in methanol (100 mL), (R)-3a (561.1 mg, 1.0 mmol) was
hexane/EtOAc = 4:1), to give the desired product ((R)-5a) (119.3 mg,
1
9
8% yield). H NMR (400 MHz, CDCl ) δ 0.93 (t, J = 7.2 Hz, 3H),
2
3
added. The solution was warmed to 70 °C for 15 h by monitoring with
TLC. Then the reaction mixture was cooled to room temperature and
concentrated under reduced pressure. The colorless precipitate was
acidified with a 1 M HCl aqueous solution at 0 °C and extracted with
ethyl acetate (15 mL × 2). The combined extracts were washed with
2.33 (d, J = 5.0 Hz, 3H), 3.29 (q, J = 5.0 Hz, 1H), 3.70 (dq, J = 9.6, 6.9
Hz, 1H), 3.86 (dq, J = 9.6, 6.9 Hz, 1H), 7.25 (d, J = 8.2 Hz, 1H), 7.29
(d, J = 8.7 Hz, 1H), 7.37−7.55 (m, 8H), 7.57−7.74 (m, 5H), 7.79 (m,
1
3
1H), 7.91 (d, J = 8.2 Hz, 2H), 7.93 (s, 1H), 7.94 (s 1H). C NMR
(100 MHz, CDCl ) Many peaks overlapped. δ 14.4, 28.8, 66.2, 127.2,
3
brine (10 mL) and dried over MgSO . The organic phase was
127.54, 127.56, 127.61, 127.91, 127.94, 128.0, 128.3, 128.5, 128.8,
129.1, 129.1, 130.0, 132.1, 132.3, 132.5, 132.6, 132.7, 133.5, 133.9,
134.8, 136.1, 137.4, 138.5, 139.6, 140.0, 140.6. Mp 214−217 °C
4
concentrated under reduced pressure, and the crude product was
purified by silica gel column chromatography (eluent: CHCl /MeOH
3
1
−1
25
D
=
5:1), to give the desired product ((R)-4a) (597.0 mg, 99% yield). H
(decomposed). IR (KBr) 3372, 3055, 1332, 1183, 1000 cm . [α]
=
1
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1
86.4 (c 1.0, CHCl , (R)). HRMS (FAB+, Magnetic sector) calcd for
(R)). HRMS (FAB+, Magnetic sector) calcd for C H O S [M +
3
33 23
5 2
+
+
C H NO S [M + H] 608.1565, found 608.1555.
H] 563.0987, found 563.0997.
35
30
5 2
25
(
R)-Ethyl 2′-(N,N-Dimethylsulfamoyl)-3,3′-diphenyl-(1,1′-bi-
N,N-Dimethylnaphthalene-2-sulfonamide (13). To a solu-
tion of naphthalene-2-sulfonyl chloride (1.13 g, 5.0 mmol) in THF, a
50% aqueous solution of dimethylamine (2.7 mL, 25 mmol) was
added at room temperature. The resultant reaction mixture was stirred
at room temperature for 1.5 h, poured into ice water, and extracted
with ethyl acetate. The organic phase was washed with brine and dried
naphthyl)-2-sulfonate ((R)-6a). A well dried Schlenk flask with a
condenser was charged with (R)-5a (30.4 mg, 0.050 mmol) and
K CO3 (13.8 mg, 1.0 mmol) under a nitrogen atmosphere. 1,2-
Dichloroethane (2 mL) was added, and the suspension was cooled to
0
tetrafluoroborate (14.8 mg, 0.10 mmol) was added portionwise (30
min), and the mixture was warmed to 90 °C for 52 h by monitoring
with TLC. Then 2 mL of saturated NH Cl aqueous solution were
poured into the reaction mixture, and the product was extracted with
ethyl acetate (10 mL × 2). The combined extracts were washed with
2
°C. Then a dichloromethane solution of trimethyloxonium
over anhydrous MgSO , and the excess solvent was removed in vacuo.
4
The resultant residue was purified by silica gel column chromatog-
raphy with hexane/chloroform (1:1) as the eluent affording 13 (1.18 g,
4
1
>99% yield). H NMR (400 MHz, CDCl
) δ 2.76 (s, 6H), 7.60−7.70
3
(m, 2H), 7.78 (dd, J = 8.7, 1.8 Hz, 1H), 7.93 (d, J = 7.5 Hz, 1H), 7.99
(m, 2H), 8.35 (s, 1H). 13C NMR (100 MHz, CDCl
) δ 37.8, 122.8,
127.4, 127.7, 128.6, 128.8, 190.3, 129.1, 132.0, 132.3, 134.6. Mp 95−96
brine (5 mL) and dried over MgSO . The organic phase was
concentrated under reduced pressure, and the crude product was
purified by silica gel column chromatography (eluent: hexane/EtOAc
=
3
4
−1
°C. IR (KBr) 3632, 3053, 3055, 2877, 2840, 1335, 1160, 1131 cm .
+
1
HRMS (FAB+, Magnetic sector) calcd for C H NO S [M + H]
4:1), to give the desired product ((R)-6a) (26.6 mg, 85% yield). H
12 14
2
2
36.0745, found 236.0755.
Potassium Naphthalene-2-sulfonate (14). A solution of 13
23.5 mg, 0.10 mmol) in THF (4 mL) under a nitrogen atmosphere
NMR (400 MHz, CDCl ) δ 0.94 (t, J = 7.3 Hz, 3H), 2.10 (s, 6H), 3.73
3
2
6
(
7
8
m, 1H), 3.90 (m, 1H), 7.27−7.32 (m, 2H), 7.33−7.50 (m, 8H),
(
.53−7.78 (m, 6H), 7.86 (s, 1H), 7.88 (d, J = 8.6 Hz, 1H), 7.90 (d, J =
.6 Hz, 1H), 7.94 (s, 1H). 13C NMR (100 MHz, CDCl ) Many peaks
was cooled to 0 °C, and a 65 wt % solution of bis(2-methoxyethoxy)-
aluminumhydride in toluene (0.15 mL, 0.50 mmol) was added. The
reaction mixture was stirred at room temperature for 5 h and then
cooled to 0 °C. With the suspension vigorously stirring, a saturated
Na SO aqueous solution was added, and the reaction mixture was
3
overlapped. δ 14.5, 34.5, 66.3, 127.2, 127.3, 127.4, 127.5, 127.6, 127.7,
1
1
2
1
27.8, 127.9, 128.4, 128.9, 129.2, 129.8, 132.1, 132.2, 132.5, 132.6,
33.1, 133.7, 134.1, 135.1, 137.5, 137.7, 139.6, 139.9, 140.7, 141.4. Mp
35−237 °C (decomposed). IR (KBr) 3057, 2927, 1355, 1325, 1183,
2
4
−
1
24
D
extracted with ethyl acetate (10 mL × 2). The combined extracts were
137 cm . [α]
= 337.5 (c 1.0, CHCl , (R)). HRMS (FAB+,
3
+
washed with brine (5 mL) and dried over MgSO . The organic phase
Magnetic sector) calcd for C H NO S [M + H] 622.1722, found
4
36
32
5 2
was concentrated under reduced pressure. The crude products were
used in the next step without further purification. To a solution of
crude products, 1 mL of N,N-dimethylformamide (DMF) was added.
622.1711.
Sodium (R)-2′-(N,N-Dimethylsulfamoyl)-3,3′-diphenyl-(1,1′-
binaphthalene)-2-sulfonate ((R)-8a). A well dried flask was
charged with (R)-6a (124.4 mg, 0.20 mmol) and NaOH (1.60 g, 40
mmol). Methanol (20 mL) was added, and the mixture was stirred at
Then O (balloon) was charged. The reaction mixture was heated to
2
6
0 °C for 16 h. The reaction mixture was cooled to room temperature
and was purified by silica gel column chromatography using CHCl /
MeOH (1:1) as the eluent to give 14 (23.9 mg, 97% yield). H NMR
70 °C for 5 h by monitoring with TLC. Then the volatiles were
3
1
removed under reduced pressure. A 2 M HCl aqueous solution was
poured into the reaction mixture, and the product was extracted with
ethyl acetate (20 mL × 3). The combined extracts were dried over
(
1
400 MHz, CD OD) δ 7.55 (m, 2H), 7.85−8.00 (m, 4H), 8.34 (s,
3
H). 13C NMR (100 MHz, d -DMSO/D O = 3:1) δ 124.0, 126.0,
6 2
1
28.5, 129.0, 129.1, 129.8, 129.9, 133.1, 134.7, 143.1. IR (KBr) 3422,
Na SO . The organic phase was concentrated, and the crude product
2
4
−1
1
1624, 1230, 1186, 1101, 1045 cm . HRMS (FAB−, Magnetic sector)
calcd for C H O S [M − K] 207.0116, found 207.0118.
(
(
7
almost quantitative yield) was used without purification. H NMR
400 MHz, CD OD) δ 2.12 (s, 6H), 6.98 (d, J = 8.7 Hz, 1H), 7.20−
.39 (m, 7H), 7.40−7,50 (m, 3H), 7.51−7.60 (m, 3H), 7.63 (d, J = 6.9
−
10
7
3
3
27
1
2
-Naphthalenesulfinic Acid (15).
H NMR (400 MHz,
CD OD) δ 7.54−7.57 (m, 2H), 7.84 (d, J = 8.3 Hz, 1H), 7.91−
3
Hz, 2H), 7.75 (s, 1H), 7.76 (s, 1H), 7.87 (d, J = 7.9 Hz, 1H), 7.88 (d, J
13
1
3
8.00 (m, 3H), 8.15 (s, 1H). C NMR (100 MHz, CD
25.0, 127.8, 128.1, 129.2, 129.8, 129.9, 134.7, 135.9, 154.3. Mp 92−96
C. IR (KBr) 3421, 3050, 2925, 1587, 1500, 1340, 1269, 1204, 1047
3
OD) δ 122.7,
=
8.2 Hz, 1H). C NMR (100 MHz, CD OD) Many peaks
3
1
overlapped. δ 35.5, 127.3, 127.4, 127.7, 128.0, 128.1, 128.2, 128.3,
°
128.4, 128.5, 128.7, 129.5, 129.6, 130.5, 130.9, 131.4, 132.8, 133.3,
133.7, 134.3, 134.5, 135.0, 135.6, 136.1, 139.2, 140.5, 143.4, 143.8,
144.6. Mp 283 °C (decomposed). IR (KBr) 3444, 3054, 2923, 1491,
1
−
1
−
cm . HRMS (ESI−, Q-TOF) calcd for C H O S [M − H]
1
1
0
7
2
91.0172, found 191.0174.
,2-Di(naphthalen-2-yl)disulfane (16). 1H NMR (400 MHz,
28
1
−1
22
D
322, 1188, 1135, 1042 cm . [α]
= 88.8 (c 1.0, CH OH, (R)).
3
CDCl ) δ 7.42−7.49 (m, 4H), 7.61−7.63 (m, 2H), 7.72−7.80 (m,
−
3
HRMS (FAB−, Magnetic sector) calcd for C H NO S [M − Na]
5
13
34
26
5 2
6
1
H), 7.98 (s, 2H). C NMR (100 MHz, CDCl ) δ 125.7, 126.3,
3
92.1252, found 592.1252.
Procedure for Preparation of Arylsulfone (R)-12. A well dried
26.6, 126.8, 127.5, 127.8, 129.1, 132.6, 133.5, 134.3. Mp 136−139 °C.
−1
IR (KBr) 3449, 3051, 2921, 1579, 1498, 1336, 1267, 1131 cm .
HRMS (EI, TOF) calcd for C H S [M] 318.0537, found 318.0539.
Schlenk flask was charged with (R)-6a (91.1 mg, 0.145 mmol) under a
nitrogen atmosphere. Methyl trifluoromethanesulfonate (2.0 mL, 23.6
mmol) was added at 0 °C, and the mixture was warmed to 100 °C for
+
20
14 2
Potassium (R)-3,3′-Diphenyl-(1,1′-binaphthyl)-2,2′-disulfo-
3f
nate ((R)-17a). A solution of (R)-8a, which was obtained from
20 h by monitoring with TLC. After the mixture cooled to room
(
R)-6a (0.20 mmol) without purification, in THF (8 mL) under a
temperature, water and then a saturated NH Cl aqueous solution (5
mL) were poured into the reaction mixture, and the product was
extracted with ethyl acetate (15 mL × 2). The combined extracts were
washed with brine (10 mL) and dried over MgSO . The organic phase
was concentrated under reduced pressure, and the crude product was
purified by silica gel column chromatography (eluent: hexane/EtOAc
=
4
nitrogen atmosphere was cooled to 0 °C, and a 65 wt % solution of
bis(2-methoxyethoxy)aluminumhydride (Red-Al) in toluene (0.90 mL,
3
.0 mmol) was added. The reaction mixture was heated to 35 °C for 3
4
h and then cooled to 0 °C. With the suspension vigorously stirring, a
saturated Na SO4 aqueous solution was added, and the reaction
2
mixture was extracted with ethyl acetate (20 mL × 3). The combined
4:1 to 2:1), to give the desired product ((R)-12) (9.7 mg, 11%
extracts were washed with brine (20 mL) and dried over MgSO . The
4
1
yield). H NMR (400 MHz, CDCl ) δ 3.45 (s, 3H), 7.28 (d, J = 8.7
organic phase was concentrated under reduced pressure. Crude
products were used in the next step without further purification. To a
solution of crude products in DMF (2 mL), powdered KOH (66 mg,
3
Hz, 1H), 7.38 (t, J = 7.8 Hz, 1H), 7.42−7.52 (m, 6H), 7.55−7.74 (m,
6
(
H), 7.95 (d, J = 8.2 Hz, 1H), 8.01−8.05 (m, 2H), 8.06 (s, 1H), 8.36
s, 1H). 13C NMR (100 MHz, CDCl ) Many peaks overlapped. δ
3
1.20 mmol) was added. Then the O (balloon) was charged. The
2
1
1
1
21.3, 121.8, 122.0, 127.0, 127.7, 127.8, 127.9, 128.0, 128.4, 128.6,
29.2, 129.3, 129.7, 130.3, 131.9, 132.2, 132.6, 133.0, 133.8, 134.0,
34.1, 134.4, 134.8, 135.4, 137.4, 138.4, 140.3. Mp 168−171 °C. IR
reaction mixture was heated to 60 °C for 38 h. The reaction mixture
was cooled to room temperature and was purified by silica gel column
chromatography using CHCl /MeOH (1:1) as the eluent to give (R)-
3
−1
23
1
(
KBr) 3060, 1361, 1303, 1185, 1168 cm . [α] = 130 (c 1.0, CHCl ,
17a (88.5 mg, 68% yield (3 steps), based on (R)-6a). H NMR (400
D
3
1
0410
dx.doi.org/10.1021/jo401848z | J. Org. Chem. 2013, 78, 10405−10413

The Journal of Organic Chemistry
Article
MHz, CD OD) δ 7.06 (d, J = 8.6 Hz, 2H), 7.18 (t, J = 8.0 Hz, 2H),
and the product was extracted with chloroform (15 mL × 2). The
combined extracts were washed brine (10 mL) and dried over MgSO4.
The organic phase was concentrated under reduced pressure, and the
crude product was purified by silica gel column chromatography
3
7
7
.26−7.35 (m, 6H), 7.41 (t, J = 7.6 Hz, 2H), 7.66 (d, J = 7.6 Hz, 4H),
.69 (s, 2H), 7.81 (d, J = 8.2 Hz, 2H). 13C NMR (100 MHz, CD OD)
3
δ 127.0 (2C), 127.1 (2C), 127.6 (4C), 127.8 (2C), 128.3 (2C), 129.2
2C), 131.4 (4C), 132.2 (2C), 134.2 (2C), 134.3 (2C), 138.1 (2C),
40.3 (2C), 140.4 (2C), 145.2 (2C). IR (KBr) 3056, 1231, 1186, 1038
(
(eluent: hexane/EtOAc = 6:1 to 3:1), to give the desired product ((S)-
1
1
21) (28.3 mg, >99% yield). H NMR (400 MHz, CDCl ) δ 3.36 (s,
3
−
1
24
cm . [α] = 91.3 (c 0.80, CH OH, (R)). HRMS (FAB+, Magnetic
3H), 7.00 (d, J = 8.7 Hz, 2H), 7.36 (t, J = 7.3 Hz, 2H), 7.66 (t, J = 7.6
D
3
+
13
sector) calcd for C H Na O S [M − 2K + 2Na + H] 611.0575,
Hz, 2H), 7.91 (d, J = 8.1 Hz, 2H), 8.51 (s, 2H). C NMR (100 MHz,
3
2
21
2
6 2
found 611.0584; (FAB−, Magnetic sector) calcd for C H NaO S
CDCl ) δ 31.5, 114.1 (2C), 127.6 (2C), 128.4 (2C), 128.7 (2C),
3
2
20
6
2
3
−
[
M − 2K + Na] 587.0599, found 587.0608.
130.7 (2C), 131.2 (2C), 135.5 (2C), 137.3 (4C), 140.8 (2C). Mp 283
1
3,3′-Diphenyl-1,1′-binaphthalene (18). H NMR (400 MHz,
°C (decomposed). IR (KBr) 3419, 1551, 1372, 1348, 1183, 1156,
−
1
25
CDCl ) δ 7.31 (t, J = 6.9 Hz, 2H), 7.37 (t, J = 7.3 Hz, 2H), 7.44−7.54
1132, 1044 cm . [α] = 131.2 (c 0.20, CHCl , (S)). HRMS (EI,
3
D
3
+
(
m, 8H), 7.79 (d, J = 6.9 Hz, 4H), 7.85 (d, J = 1.8 Hz, 2H), 8.01 (d, J
TOF) calcd for C H Br NO S [M] 564.8653, found 564.8657.
21 13 2 4 2
=
8.2 Hz, 2H), 8.18 (s, 2H). 13C NMR (100 MHz, CDCl ) δ 125.8
Representative Procedure for Preparation of 3. To a two-
necked flask equipped with a condenser were placed (S)-21 (567 mg,
1.0 mmol), phenyl boronic acid (366 mg, 3.0 mmol), Pd(PPh ) (116
3
(
1
(
2C), 126.2 (2C), 126.4 (2C), 126.5 (2C), 127.5 (4C), 127.6 (2C),
27.7 (2C), 128.6 (2C), 129.0 (4C), 132.1 (2C), 134.0 (2C), 138.1
3
4
−1
2C), 139.0 (2C), 140.8 (2C). IR (neat) 3056, 1595, 1495, 1448 cm .
mg, 0.10 mmol), K CO (1.38 g, 10 mmol), THF (20 mL), and water
2 3
+
HRMS (EI, TOF) calcd for C H [M] 406.1722, found 406.1729.
(5 mL). The mixture was heated at 85 °C for 12 h. After the mixture
32
22
(
R)-3,3′-Diphenyl-(1,1′-binaphthyl)-2,2′-disulfonic Acid ((R)-
cooled to room temperature, a saturated NH Cl aqueous solution (5
4
3
f
1
a). A solution of (R)-17a (37.9 mg, 0.059 mmol) in methanol (1
mL) was poured into the reaction mixture, and the product was
extracted with chloroform (30 mL × 2). The combined extracts were
washed brine (30 mL) and dried over Na SO . The organic phase was
3
mL) was passed through a cation exchange column (100 cm ,
Amberlite IR120 ion-exchange resin. The cation exchange resin is
converted to the H form by washing with 3 M HCl and then water, in
2
4
+
concentrated under reduced pressure, and the crude product was
purified by silica gel column chromatography (eluent: hexane/EtOAc
advance.). The eluate was concentrated in vacuo. The remaining water
was removed by azeotropic distillation with toluene. The resultant
=
6:1 to 3:1), to give the desired product ((S)-3a) (490 mg, 87%
white-brown powder of (R)-1a was dried in vacuo for 12 h (33.4 mg,
yield). (S)-3b and (S)-3c were obtained in the respective yield of 89%
and 90%.
1
>
99% yield). H NMR (400 MHz, CD OD) δ 7.07 (d, J = 8.6 Hz,
3
2
2
H), 7.25 (t, J = 7.3 Hz, 2H), 7.29−7.43 (m, 6H), 7.50 (t, J = 6.9 Hz,
(
S)-N-Methyl-3,3′-di(biphenyl)-(1,1′-binaphthyl)-2,2′-sulfonimide
1
H), 7.61 (d, J = 7.0 Hz, 4H), 7.80 (s, 2H), 7.89 (d, J = 7.8 Hz, 2H).
((S)-3b). 89% yield. H NMR (400 MHz, CDCl ) δ 3.00 (s, 3H), 7.27
3
1
3
C NMR (100 MHz, CD OD) δ 127.5 (2C), 127.6 (2C), 127.9 (4C),
(d, J = 8.7 Hz, 2H), 7.35 (t, J = 7.3 Hz, 2H), 7.39−7.49 (m, 6H),
3
128.6 (2C), 128.7 (2C), 129.0 (2C), 131.0 (4C), 132.8 (2C), 134.0
7.51−7.60 (m, 4H), 7.62−7.74 (m, 10H), 8.00 (d, J = 8.2 Hz, 2H),
(
2C), 134.5 (2C), 138.4 (2C), 138.6 (2C), 140.0 (2C), 144.2 (2C).
8.07 (s, 2H). 13C NMR (100 MHz, CDCl ) Many peaks overlapped. δ
3
Mp 216−219 °C (decomposed). IR (KBr) 3420, 3053, 1229, 1182,
30.7, 125.8, 126.5, 127.1, 127.4, 128.2, 128.4, 128.7, 129.1, 129.9,
−
1
24
1
035 cm . [α]
= 121 (c 1.0, MeOH, (R)). HRMS (FAB+,
130.8, 131.6, 131.9, 133.8, 134.4, 137.5, 138.7, 138.9, 140.3, 140.5. Mp
D
+
−1
Magnetic sector) calcd for C H O S [M] 566.0858, found
194−196 °C. IR (KBr) 3028, 1576, 1487, 1369, 1349, 1177 cm .
3
2
22
6 2
23
5
66.0862.
R)-Diethyl 3,3′-Diphenyl-(1,1′-binaphthyl)-2,2′-disulfonate
(R)-19a). A well dried Schlenk flask was charged with (R)-1a (31.0
mg, 0.055 mmol) and K CO (69.1 mg, 0.50 mmol) under a nitrogen
[α] = 12.8 (c 0.50, CHCl , (S)). HRMS (FAB+, Magnetic sector)
D
3
+
(
calcd for C H NO S [M] 713.1694, found 713.1702.
45 31 4 2
(
(S)-N-Methyl-3,3′-di(terphenyl)-(1,1′-binaphthyl)-2,2′-sulfoni-
1
mide ((S)-3c). 90% yield. H NMR (400 MHz, CDCl ) δ 3.00 (s, 3H),
2
3
3
atmosphere. Dichloromethane (2 mL) was added, and the suspension
7.30−7.40 (m, 6H), 7.40−7.50 (m, 10H), 7.66−7.76 (m, 14H), 7.87
(m, 2H), 8.01 (d, J = 8.2 Hz, 2H), 8.16 (s, 2H). 13C NMR (100 MHz,
was cooled to 0 °C. Then a 1.0 M CH Cl solution of triethyloxonium
2
2
tetrafluoroborate (0.50 mL, 0.50 mmol) was added, and the mixture
CDCl ) Many peaks overlapped. δ 30.7, 125.3, 126.4, 127.2, 127.4,
3
was warmed to room temperature for 15 h by monitoring with TLC.
127.5, 127.6, 128.2, 128.3, 128.8, 128.9, 130.0, 131.7, 132.0, 133.9,
Then 5 mL of saturated NH Cl aqueous solution were poured into the
reaction mixture, and the product was extracted with ethyl acetate (15
134.4, 137.6, 139.1, 140.6, 140.7, 141.2. Mp 194−196 °C. IR (KBr)
4
−1
24
2940, 1593, 1574, 1496, 1370, 1349, 1177, 1028 cm . [α] = −30.0
D
+
mL × 2). The combined extracts were washed with brine (10 mL) and
(c 0.50, CHCl , (S)). HRMS (EI, TOF) calcd for C H NO S [M]
3
57 39
4 2
dried over MgSO . The organic phase was concentrated under reduced
865.2321, found 865.2336.
4
pressure, and the crude product was purified by silica gel column
chromatography (eluent: hexane/EtOAc = 3:1), to give the desired
product ((R)-19a) (28.8 mg, 84% yield). Optical purity was
determined by HPLC analysis, and >99% ee was confirmed. [IA,
Sodium (S)-2′-(N-Methylsulfamoyl)-3,3′-di(biphenyl)-(1,1′-
1
binaphthyl)-2-sulfonate ((S)-4b). 96% yield. H NMR (400 MHz,
d
-THF) δ 2.10 (s, 3H), 4.30 (br, 1H), 6.90 (d, J = 8.6 Hz, 1H), 7.12
8
(t, J = 7.3 Hz, 1H), 7.16−7.22 (m, 2H), 7.23−7.32 (m, 2H), 7.32−
13
hexane/i-PrOH = 9:1, 1.0 mL/min, t = 9.0 min (S), 16.9 min (R).
7.46 (m, 6H), 7.55−7.84 (m, 16H). C NMR (100 MHz, d -THF)
8
R
1
(
S)-19a was prepared from (S)-1a by the same procedure.] H NMR
Many peaks overlapped. δ 28.8, 126.1, 126.3, 126.9, 127.3, 127.6,
128.1, 128.2, 128.4, 129.0, 129.4, 129.6, 131.0, 131.4, 131.7, 132.5,
132.6, 133.8, 134.2, 134.4, 135.5, 135.9, 137.6, 139.3, 139.8, 140.8,
141.1, 141.2, 141.3, 141.9, 142.7, 144.0. Mp 284−286 °C. IR (KBr)
(
3
7
400 MHz, CDCl ) δ 0.94 (t, J = 6.9 Hz, 6H), 3.66−3.75 (m, 2H),
3
.79−3.88 (m, 2H), 7.25 (d, J = 8.7 Hz, 2H), 7.39−7.75 (m, 14H),
.92 (d, J = 8.2 Hz, 2H), 7.96 (s, 2H). 13C NMR (100 MHz, CDCl )
3
−
1
22
Many peaks overlapped. δ 14.5, 66.3, 127.5, 127.8, 127.9, 128.1, 129.3,
3373, 3065, 1486, 1393, 1329, 1229, 1203, 1042 cm . [α]
(c 0.20, CHCl , (S)). HRMS (ESI−, Q-TOF) calcd for C45H32NO S
5 2
D
= −81.9
1
3
1
29.7, 130.3, 132.2, 132.7, 133.0, 134.1, 137.7, 138.9, 140.6. IR (KBr)
3
−1
24
−
056, 2984, 2256, 1580, 1493, 1444, 1354, 1185, 1001 cm . [α]
=
[M − Na] 730.1727, found 730.1723.
D
12.0 (c 0.20, CHCl , (R)). HRMS (FAB+, Magnetic sector) calcd for
Sodium (S)-2′-(N-Methylsulfamoyl)-3,3′-di(terphenyl)-(1,1′-
3
+
1
C H O S [M + H] 623.1562, found 623.1563.
binaphthyl)-2-sulfonate ((S)-4c). 90% yield. H NMR (400 MHz,
36
31
6 2
(
S)-N-Methyl-3,3′-dibromo-(1,1′-binaphthyl)-2,2′-sulfoni-
d -THF) δ 2.18 (s, 3H), 4.10 (br, 1H), 7.03 (d, J = 8.7 Hz, 1H), 7.14
8
mide ((S)-21). A well dried Schlenk was charged with (S)-3,3′-
(m, 2H), 7.20 (t, J = 7.8 Hz, 1H), 7.24−7.50 (m, 14H), 7.68−8.05 (m,
4c
13
dibromo-1,1′-binaphthyl-2,2′-sulfonimide ((S)-20) (27.7 mg, 0.050
mmol) and K CO (20.7 mg, 0.15 mmol) under a nitrogen
18H). C NMR (100 MHz, d -THF) Many peaks overlapped. δ 28.9,
8
124.4, 125.6, 127.3, 127.6, 127.9, 128.0, 128.1, 128.3, 128.4, 129.0,
129.4, 129.6, 129.7, 132.6, 133.1, 134.0, 134.2, 134.3, 136.3, 136.5,
138.3, 139.5, 139.9, 140.8, 141.4, 141.7, 141.9, 142.2, 143.7, 145.2. Mp
282−284 °C. IR (KBr) 3374, 3058, 1593, 1496, 1330, 1232, 1169,
2
3
atmosphere. Dichloromethane (2 mL) was added, and the suspension
was cooled to 0 °C. Trimethyloxonium tetrafluoroborate (22.2 mg,
0.15 mmol) was added, and the mixture was warmed to room
−
1
23
temperature for 20 h by monitoring with the TLC. Then a saturated
1040 cm . [α] = −125.2 (c 0.20, CHCl , (S)). HRMS (ESI−, Q-
−
D
3
NH Cl aqueous solution (5 mL) was poured into the reaction mixture,
TOF) calcd for C H NO S [M − Na] 882.2353, found 882.2367.
4
57 40
5 2
1
0411
dx.doi.org/10.1021/jo401848z | J. Org. Chem. 2013, 78, 10405−10413

The Journal of Organic Chemistry
Article
(
S)-Ethyl 2′-(N-Methylsulfamoyl)-3,3′-di(biphenyl)-(1,1′-bi-
132.7, 133.1, 133.3, 133.7, 135.0, 137.6, 138.7, 139.8, 140.0, 140.5,
140.7, 140.9, 141.1, 141.5, 142.8, 143.2, 144.7. Mp 293−296 °C
(decomposed). IR (KBr) 3407, 3033, 1594, 1497, 1319, 1188, 1041
1
naphthyl)-2-sulfonate ((S)-5b). 78% yield. H NMR (400 MHz,
CDCl ) δ 0.95 (t, J = 7.8 Hz, 3H), 2.38 (d, J = 4.9 Hz, 3H), 3.48 (q, J
3
−
1
23
=
5.0 Hz, 1H), 3.77 (dq, J = 10.1, 7.1 Hz, 1H), 3.92 (dq, J = 10.1, 7.1
Hz, 1H), 7.25−7.53 (m, 10H), 7.60−7.83 (m, 13H), 7.88 (d, J = 7.8
Hz, 1H), 7.94 (d, J = 8.2 Hz, 2H), 7.99 (s, 1H), 8.01 (s, 1H). 13
NMR (100 MHz, CDCl ) Many peaks overlapped. δ 14.9, 28.8, 66.3,
cm . [α] = −155.2 (c 0.20, CHCl , (S)). HRMS (FAB−, Magnetic
−
D
3
sector) calcd for C H NO S [M−Na] 896.2504, found 896.2528.
58
42
5 2
C
Potassium (S)-3,3′-Di(biphenyl)-(1,1′-binaphthyl)-2,2′-disul-
1
fonate ((S)-17b). 69% yield. H NMR (400 MHz, CD OD) δ 7.04
3
3
1
1
1
1
1
26.0, 126.6, 126.9, 127.1, 127.2, 127.3, 127.4, 127.6, 127.7, 127.8,
28.0, 128.1, 128.8, 128.9, 129.0, 129.2, 129.6, 130.6, 132.2, 132.4,
32.7, 132.8, 133.6, 134.1, 134.8, 135.9, 137.2, 138.7, 139.1, 139.8,
40.0, 140.3, 140.7, 141.2. Mp 163−165 °C. IR (KBr) 3373, 3030,
(m, 2H), 7.18 (t, J = 8.2 Hz, 2H), 7.30 (t, J = 7.3 Hz, 2H), 7.42 (t, J =
7.6 Hz, 6H), 7.59 (d, J = 8.2 Hz, 4H), 7.66 (d, J = 7.8 Hz, 4H), 7.72−
7.81 (m, 6H), 7.83 (d, J = 7.8 Hz, 2H). 13C NMR (100 MHz,
CD OD) Many peaks overlapped. δ 126.4, 127.2, 127.9, 128.0, 128.1,
3
−1
23
487, 1353, 1331, 1183 cm . [α] = −76.0 (c 0.20, CHCl , (S)).
128.4, 129.2, 129.7, 131.7, 132.3, 134.2, 134.4, 138.3, 139.8, 140.2,
D
3
+
−1
HRMS (FAB+, Magnetic sector) calcd for C H NO S [M + H]
142.7, 144.2. IR (KBr) 3371, 1620, 1485, 1220, 1175, 1036 cm .
47
38
5 2
[α]D23 = −10.0 (c 0.20, CH OH, (S)). HRMS (FAB−, Magnetic
7
60.2191, found 760.2203.
3
−
(
S)-Ethyl 2′-(N-Methylsulfamoyl)-3,3′-di(terphenyl)-(1,1′-bi-
sector) calcd for C H NaO S [M − 2K + Na] 739.1225, found
44
28
6 2
1
naphthyl)-2-sulfonate ((S)-5c). 78% yield. H NMR (400 MHz,
CDCl ) δ 0.85 (t, J = 7.0 Hz, 3H), 2.40 (d, J = 5.0 Hz, 3H), 3.56 (q, J
=
739.1205.
3
Potassium (S)-3,3′-Di(terphenyl)-(1,1′-binaphthyl)-2,2′-di-
1
5.5 Hz, 1H), 3.75 (m, 1H), 3.86 (m, 1H), 7.29−7.54 (m, 16H),
sulfonate ((S)-17c). 74% yield. H NMR (400 MHz, CD OD) δ
3
7
1
.59−7.67 (m, 2H), 7.70−7.80 (m, 8H), 7.82−8.00 (m, 7H), 8.03 (m,
7.10 (m, 2H), 7.24 (t, J = 7.3 Hz, 2H), 7.32 (t, J = 7.3 Hz, 4H), 7.40−
H), 8.08 (s, 1H), 8.10 (s 1H). 13C NMR (100 MHz, CDCl ) Many
13
7.53 (m, 10H), 7.73−7.85 (m, 10H), 7.86−8.00 (m, 8H). C NMR
3
peaks overlapped. δ 14.6, 29.2, 66.4, 125.3, 126.2, 126.9, 127.5, 127.7,
(100 MHz, CD OD) Many peaks overlapped. δ 124.8, 127.4, 128.1,
3
1
1
1
27.9, 128.5, 128.6, 129.2, 129.3, 129.4, 129.6, 132.6, 132.8, 132.9,
33.0, 133.9, 134.3, 135.2, 136.3 137.6, 139.0, 140.1, 140.3, 140.4,
40.8, 141.0, 141.1, 141.2, 141.4, 141.7, 141.8, 142.0. Mp 193−194 °C.
128.4, 128.5, 129.2, 129.3, 129.7, 132.5, 134.3, 134.4, 138.3, 139.8,
−1
141.4, 143.0, 146.0. IR (KBr) 3406, 1594, 1215, 1182, 1038 cm .
2
3
[α]
= −72.0 (c 0.20, CH OH, (S)). HRMS (FAB−, Magnetic
D
3
−1
22
−
IR (KBr) 3376, 3034, 1593, 1496, 1330, 1182 cm . [α] = −112.0
sector) calcd for C56
891.1841.
H36NaO S [M − 2K + Na] 891.1851, found
6 2
D
(c 0.20, CHCl , (S)). HRMS (FAB+, Magnetic sector) calcd for
3
+
C H NO S [M + H] 912.2817, found 912.2814.
(S)-3,3′-Di(biphenyl)-(1,1′-binaphthyl)-2,2′-disulfonic Acid
1
59
46
5 2
(
S)-Ethyl 2′-(N,N-Dimethylsulfamoyl)-3,3′-di(biphenyl)-(1,1′-
((S)-1b). >99% yield. H NMR (400 MHz, CD OD) δ 7.10 (d, J =
3
1
binaphthyl)-2-sulfonate ((S)-6b). >99% yield. H NMR (400 MHz,
CDCl ) δ 0.97 (t, J = 6.9 Hz, 3H), 2.16 (s, 6H), 3.79 (dq, J = 10.1, 7.3
8.6 Hz, 2H), 7.27 (t, J = 7.0 Hz, 2H), 7.33 (t, J = 7.3 Hz, 2H), 7.44 (t,
J = 7.8 Hz, 4H), 7.51 (t, J = 7.8 Hz, 2H), 7.62−7.67 (m, 4H), 7.68−
7.74 (m, 8H), 7.86 (s, 2H), 7.91 (d, J = 8.2 Hz, 2H). 1 C NMR (100
3
3
Hz, 1H), 3.79 (dq, J = 10.1, 7.3 Hz, 1H), 7.30−7.52 (m, 10H), 7.58−
13
7
.80 (m, 14H), 7.79−7.96 (m, 3H), 7.99 (s, 1H). C NMR (100
MHz, CD OD) Many peaks overlapped. δ 126.5, 127.7, 127.9, 128.1,
3
MHz, CDCl ) Many peaks overlapped. δ 14.5, 34.5, 66.3, 126.0, 126.4,
128.7, 128.8, 129.1, 129.8, 131.6, 132.9, 134.1, 134.6, 138.5, 138.7,
3
1
1
1
1
26.9, 127.1, 127.4, 127.5, 127.6, 127.7, 127.9, 128.0, 128.8, 128.9,
29.2, 130.3, 132.2, 132.3, 132.5, 132.8, 133.1, 133.7, 134.1, 135.2,
37.1, 137.4, 139.8, 139.9, 140.1, 140.3, 140.4, 140.5, 140.7. Mp 171−
139.7, 140.6, 142.4, 143.3. Mp 220−224 °C (decomposed). IR (KBr)
−1
22
3382, 1697, 1486, 1220, 1164, 1033 cm . [α]
= −20.8 (c 1.0,
D
MeOH, (S)). HRMS (FAB−, Magnetic sector) calcd for C44
H O S
29 6 2
−1
24
−
73 °C. IR (KBr) 3029, 1487, 1355, 1324, 1136, 1067 cm . [α]
=
[M − H] 717.1406, found 717.1391.
D
−
91.9 (c 0.20, CHCl , (S)). HRMS (FAB+, Magnetic sector) calcd for
(S)-3,3′-Di(terphenyl)-(1,1′-binaphthyl)-2,2′-disulfonic Acid
3
1
+
(
(S)-1c). >99% yield. H NMR (400 MHz, CD OD) δ 7.16 (br,
C H NO S [M + H] 774.2348, found 774.2359.
3
48
40
5 2
2
H), 7.27 (t, J = 7.3 Hz, 2H), 7.32 (t, J = 7.3 Hz, 4H), 7.40−7.53 (m,
13
(
S)-Ethyl 2′-(N,N-Dimethylsulfamoyl)-3,3′-di(terphenyl)-
1
(
1,1′-binaphthyl)-2-sulfonate ((S)-6c). 98% yield. H NMR (400
10H), 7.73−7.85 (m, 10H), 7.86−8.00 (m, 8H). C NMR (100 MHz,
CD OD) Many peaks overlapped. δ 124.9, 127.6, 128.2, 128.4, 128.5,
MHz, CDCl ) δ 0.86 (t, J = 6.9 Hz, 3H), 2.20 (s, 6H), 3.77 (m, 1H),
3
3
3
(
.90 (m, 1H), 7.30−7.52 (m, 16H), 7.59−7.68 (m, 2H), 7.70−8.03
128.6, 129.2, 129.3, 129.7, 132.7, 134.2, 134.5, 139.9, 141.5, 142.8,
m, 17H), 8.09 (s, 1H). 13C NMR (100 MHz, CDCl ) Many peaks
145.4. Mp 232−235 °C (decomposed). IR (KBr) 3389, 1497, 1218,
3
−
1
23
overlapped. δ 14.4, 34.8, 66.2, 124.7, 125.1, 126.0, 127.2, 127.3, 127.4,
1186, 1035 cm . [α]
D
= −69.2 (c 0.20, CH OH, (S)). HRMS
3
−
1
1
1
1
27.5, 127.7, 127.9, 128.0, 128.9, 129.0, 129.1, 129.3, 132.3, 132.7,
33.1, 133.7, 134.1, 135.2, 137.3, 137.4, 139.9, 140.1, 140.6, 140.8,
40.9, 141.2, 141.6, 142.3. Mp 189−191 °C. IR (KBr) 3035, 1593,
(FAB−, Magnetic sector) calcd for C56H O S [M−H] 869.2032,
37 6 2
found 869.2014.
Procedure for Improved Method by Double N,O-Methyl-
ation of (S)-4b and Hydrolysis to (S)-8b. A well dried Schlenk flask
with a condenser was charged with (S)-4b (550 mg, 0.73 mmol) and
−1
23
D
576, 1497, 1355, 1322, 1183, 1137 cm . [α]
= −93.9 (c 0.20,
CHCl , (S)). HRMS (FAB+, Magnetic sector) calcd for C H NO S
3
60 48
5 2
+
K CO3 (1.01 g, 7.3 mmol) under a nitrogen atmosphere. 1,2-
[
M+H] 926.2974, found 926.2969.
Sodium (S)-2′-(N,N-Dimethylsulfamoyl)-3,3′-di(biphenyl)-
2
Dichloroethane (20 mL) was added, and the suspension was cooled to
0 °C. Then a dichloromethane solution (5 mL) of trimethyloxonium
tetrafluoroborate (650 mg, 4.4 mmol) was added portionwise (30
min), and the mixture was warmed to 90 °C for 15 h by monitoring
1
(
1,1′-binaphthyl)-2-sulfonate ((S)-8b). H NMR (400 MHz, d -
8
THF) δ 1.91 (s, 6H), 6.77 (br, 1H), 6.90 (d, J = 8.7 Hz, 1H), 7.08−
7
7
.40 (m, 12H), 7.42−7.50 (m, 4H), 7.50−7.56 (m, 4H), 7.60 (d, J =
.8 Hz, 1H), 7.64 (s, 1H), 7.75 (br, 2H), 7.80−7.86 (m, 2H).
13
C
with TLC. Then 20 mL of saturated NH Cl aqueous solution was
4
NMR (100 MHz, d -THF) Many peaks overlapped. δ 33.9, 124.9,
poured into the reaction mixture at room temperature, and the
product was extracted with dichloromethane (20 mL × 2). The
8
1
1
1
2
1
25.8, 126.5, 126.6, 126.7, 126.8, 127.1, 127.5, 127.7, 128.3, 128.4,
28.7, 130.8, 131.4, 131.7, 131.9, 132.8, 132.9, 133.1, 133.9, 134.3,
34.8, 137.8, 138.7, 138.9, 140.3, 140.5, 140.8, 141.4, 142.8, 143.0. Mp
89−292 °C (decomposed). IR (KBr) 3422, 3029, 1619, 1487, 1322,
combined extracts were dried over Na
concentrated under reduced pressure, and the crude products (i.e., the
mixture of R*SO Me and R*SO H) were used without further
SO . The organic phase was
2
4
3
3
−1
23
D
190, 1135, 1041 cm . [α] = 107.2 (c 0.20, CHCl , (S)). HRMS
purification. To the residue obtained, a solution of NaOH (5.84 g, 200
mmol) in methanol (70 mL) was added. The solution was warmed to
70 °C for 12 h by monitoring with the TLC. Then the reaction
mixture was cooled to room temperature and concentrated under
reduced pressure. The colorless precipitate was acidified with 1 M HCl
aqueous solution at 0 °C and extracted with ethyl acetate (20 mL × 3).
The combined extracts were washed with brine (10 mL) and dried
over Na SO . The organic phase was concentrated under reduced
3
−
(
FAB−, Magnetic sector) calcd for C H NO S [M−Na] 744.1878,
46
34
5 2
found 744.1860.
Sodium (S)-2′-(N,N-Dimethylsulfamoyl)-3,3′-di(terphenyl)-
1
(
1,1′-binaphthyl)-2-sulfonate ((S)-8c). H NMR (400 MHz, d -
8
THF) δ 2.00 (s, 6H), 6.98 (d, J = 8.7 Hz, 1H), 7.12−7.35 (m, 13H),
7
13
.35−7.46 (m, 4H), 7.62−7.88 (m, 18H). C NMR (100 MHz, d -
8
THF) Many peaks overlapped. δ 34.5, 123.2, 124.0, 126.0, 126.6,
26.9, 127.0, 127.1, 127.3, 127.5, 128.2, 128.5, 128.7, 129.0, 131.9,
2
4
1
pressure, and the crude product was purified by silica gel column
1
0412
dx.doi.org/10.1021/jo401848z | J. Org. Chem. 2013, 78, 10405−10413

The Journal of Organic Chemistry
Article
chromatography (eluent: CHCl /MeOH = 5:1), to give the desired
(11) Nayak, S. K. Synthesis 2000, 1575.
3
product ((S)-8b) (444 mg, 79% yield).
(12) (a) Knowles, H. S.; Parsons, A. F.; Pettifer, R. M.; Rickling, S.
Tetrahedron 2000, 56, 979. (b) Parsons, A. F.; Pettifer, R. M.
Tetrahedron Lett. 1996, 37, 1667.
ASSOCIATED CONTENT
■
(
13) (a) Alonso, E.; Ramon
14355. (b) Nyasse, B.; Grehn, L.; Ragnarsson, U. Chem. Commun.
997, 1017.
14) Nagashima, H.; Ozaki, N.; Washiyama, M.; Itoh, K. Tetrahedron
Lett. 1985, 26, 657.
(15) (a) Abad, A.; Mellier, D.; Pet
́
, D. J.; Yus, M. Tetrahedron 1997, 53,
*
S
Supporting Information
1
13
H and C NMR spectra of all new compounds. This material
1
(
is available free of charge via the Internet at http://pubs.acs.org.
AUTHOR INFORMATION
Corresponding Author
E-mail: ishihara@cc.nagoya-u.ac.jp.
■
̀
e, J. P.; Portella, C. Tetrahedron
Lett. 1971, 12, 4555. (b) Hamada, T.; Nishida, A.; Yonemitsu, O. J.
*
Am. Chem. Soc. 1986, 108, 140.
(16) Horner, L.; Neumann, H. Chem. Ber. 1965, 98, 3462.
Notes
(17) (a) Fukuyama, T.; Jow, C.-K.; Cheung, M. Tetrahedron Lett.
The authors declare no competing financial interest.
1
995, 36, 6373. (b) Fukuyama, T.; Cheung, M.; Jow, C.-K.; Hidai, Y.;
Kan, H. Tetrahedron Lett. 1997, 38, 5831. (c) Kan, T.; Fukuyama, T.
Chem. Commun. 2004, 353.
ACKNOWLEDGMENTS
■
This work was partially supported by Scientific Research on
Innovative Areas “Advanced Molecular Transformations by
Organocatalysts” (24105512) from the MEXT, Japan.
(18) Nakamura, S.; Toru, T. Sci. Synth. 2007, 31a, 879.
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0413
dx.doi.org/10.1021/jo401848z | J. Org. Chem. 2013, 78, 10405−10413