Copper(II) triflate-catalyzed intramolecular hydroamination of homoallylic amino alcohols as an expedient route to trans-2,5-dihydro-1H-pyrroles and 1,2-dihydroquinolines

Article abstract of DOI:10.1002/adsc.201000450

A new efficient synthetic route to trans-2,5-dihydro-1H-pyrroles and 1,2-dihydroquinolines that relies on copper(II) triflate-catalyzed intramolecular hydroamination of homoallylic amino alcohols under mild and operationally straightforward conditions is

Full text of DOI:10.1002/adsc.201000450

FULL PAPERS
DOI: 10.1002/adsc.201000450
Copper(II) Triflate-Catalyzed Intramolecular Hydroamination of
Homoallylic Amino Alcohols as an Expedient Route to trans-2,5-
Dihydro-1H-pyrroles and 1,2-Dihydroquinolines
Weidong Rao,a Prasath Kothandaraman,a Chii Boon Koh,a
and Philip Wai Hong Chana,*
a
Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological
University, Singapore 637371, Singapore
Fax : (+65)-6791-1961; e-mail: waihong@ntu.edu.sg
Received: June 9, 2010; Published online: September 14, 2010
Supporting information for this article is available on the WWW under
http://dx.doi.org/10.1002/adsc.201000450.
Abstract: A new efficient synthetic route to trans- responding 1,2-dihydroquinoline products in excel-
2,5-dihydro-1H-pyrroles and 1,2-dihydroquinolines lent yields up to 99% and with complete chemoselec-
that relies on copper(II) triflate-catalyzed intramo- tivity. The mechanism is suggested to involve cop-
lecular hydroamination of homoallylic amino alco- per(II)-mediated dehydration of the homoallylic
hols under mild and operationally straightforward amino alcohol. Protonation of the resultant cop-
conditions is described. For reactions leading to the per(II)-activated aminodiene is then thought to trig-
trans-2,5-dihydro-1H-pyrrole product, yields of 52– ger subsequent intramolecular hydroamination to
83% along with trans selectivities up to >99:1 dr give the partially hydrogenated nitrogen heterocycle.
and ee values up to 97% were accomplished from
enantioenriched 1-(tosylamino)pent-4-en-2-ols rang-
ing from 91–99% ee. Without the need for inert and Keywords: aminodienes; copper catalysis; 2,5-dihy-
moisture-free conditions, reactions involving 1-[2- dro-1H-pyrroles; 1,2-dihydroquinolines; intramolecu-
(tosylamino)phenyl]but-3-en-1-ols afforded the cor- lar hydroamination
Introduction
AgOTf-catalyzed tandem amination/ring expansion of
cyclopropylmethanols with aryl sulfonamides that was
AHCTUNGTRENNUNG
Intramolecular hydroaminations, the formal addition thought to putatively proceed via intramolecular hy-
of a nitrogen and hydrogen atom to an unsaturated droamination of an aminoalkene intermediate.[9d] As
À
C C bond, mediated typically in the presence of tran- part of an ongoing program to develop such reac-
sition metal catalysts provide a convenient synthetic tions,[9] our discovery that Cu
(OTf)2 can effect intra-
route to nitrogen-containing heterocycles.[1–7] Al- molecular hydroamination of aminodienes generated
though this has led to a myriad of studies devoted to in situ from the respective homoallylic amino alcohols
this reaction, the majority have been focused on intra- 1 and 3 is reported herein (Scheme 1). This process
molecular hydroamination of amino-tethered alkenes, delivers an expedient route to trans-2,5-dihydro-1H-
alkynes and allenes.[1–4] In contrast and despite recent pyrroles 2 and 1,2-dihydroquinolines 4, which are
notable advances made in metal-mediated intermolec- common building blocks in organic synthesis and key
ular hydroaminations of dienes,[6] synthetic methods components in a myriad of bioactive compounds.[11]
reporting the analogous intramolecular version of this The trans-pyrrolidine adducts were also obtained with
reaction with aminodienes have remained sparse.[5]
high ee values that demonstrated efficient chirality
Over the last decade, the use of alcohol pro-electro- transfer from the enantioenriched starting materials
À
philes in Lewis acid-catalyzed C N bond formation to the products. In addition, the reactions were ac-
strategies has received an increasing amount of atten- complished with a readily available and inexpensive
tion.[8–10] For example, we recently reported an effi- copper catalyst that did not need additives and/or a
cient method for pyrrolidine synthesis based on AuCl/ ligand support or exclusion of air and moisture for re-
Adv. Synth. Catal. 2010, 352, 2521 – 2530
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Weidong Rao et al.
Table 1. Optimization of the reaction conditions.[a]
FULL PAPERS
Entry Catalyst
Solvent
Yield [%][b] dr[c]
>20:1[d]
1
Cu
G
ACHTUNGTRENNUNG
2[e]
3[f]
4
Cu
Cu
U
A
>20:1
–
[g]
A
–
Cu
N
PhMe
MeNO2
MeCN
THF
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
ACHTUNGTRENNUNG
E
ACHTUNGTRENNUNG
59
21
>20:1
>20:1
–
–
–
–
–
5
ACHTUNGTRENNUNG
[g]
6
A
–
–
–
–
–
[g]
[g]
[g]
[g]
7
A
8
A
9
CuOTf
CuI
10
11
12
13
14
15
16
17
18
19
20
Bi
In(OTf)3
Sc(OTf)3
Yb(OTf)3
A
>20:1
>20:1
Scheme 1. Intramolecular hydroamination of homoallylic
amino alcohols catalyzed by CuACTHNURTGNENG(U OTf)2.
N
[h]
N
A
9
–
–
–
[h]
U
A
actions leading to the construction of 4. While copper
complexes have recently gained momentum as a po-
tentially more ecologically benign hydroamination
catalyst, their synthetic utility has often been offset by
the need for additives and/or ligands under inert and
moisture-free conditions.[3]
AgOTf
A
>20:1
>20:1
>20:1
AuCl/AgOTf
AuCl3/AgOTf
FeCl3
TfOH
Tf2NH
A
A
[g]
A
–
–
–
[h]
[h]
G
ACHTUNGTRENNUNG
[a]
All reactions were performed at 808C for 15 h with
1a:catalyst ratio=20:1.
Isolated yield.
Determination of trans product dr was based on
1H NMR analysis of the crude mixture.
Product obtained in 93% ee based on chiral HPLC analy-
sis.
Reaction conducted without the exclusion of air or mois-
ture.
[b]
[c]
Results and Discussion
We began by examining the intramolecular hydroami-
nation of cis-(À)-1a, prepared from l-valine in >20:1
dr and 97% ee following literature methods, by a vari-
ety of Lewis and Brønsted acid catalysts to establish
the reaction conditions (Table 1). The structure and
cis stereochemistry of the starting alcohol were deter-
mined by NMR measurements and X-ray crystal
structure analysis of a closely related adduct (vide
infra). This revealed that treating cis-(À)-1a in 1,2-di-
[d]
[e]
[f]
Reaction conducted in the presence of 10 mol% K2CO3.
No reaction based on TLC and 1H NMR analysis and
near quantitative recovery of the starting alcohol.
Product dr could not be determined due to overlapping
[g]
[h]
1
impurity signals in the H NMR spectrum of the crude
mixture.
chloroethane with 5 mol% of CuACTHNUTRGNEUNG(OTf)2 at 808C for
15 h gave the best result, furnishing trans-(+)-2a as
the sole product in 70% yield, >20:1 dr trans selectiv-
ity and 93% ee (entry 1). The structure and trans ste- tries 8–20). Notably, the lower catalytic activity ob-
reochemistry of the pyrrolidine product were deter- served in reactions in the presence of TfOH and
mined by NMR measurements and X-ray crystal other metal triflates also provided evidence to dis-
structure analysis of two closely related products count a process mediated solely by the Brønsted acid
(vide infra). Lower product yields were obtained (entries 7, 9–17 and 18).[7,12]
when the reaction was repeated under atmospheric
conditions or in PhMe or MeNO2 as solvent (en- turned our attention to the reactions of a variety of
tries 2, 4 and 5). In contrast, the introduction of a cat- enantioenriched cis-1-(tosylamino)pent-4-en-2-ols
To define the scope of the present procedure, we
alytic amount of inorganic base or the use of MeCN ranging from 91–99% ee (Table 2). The structure, cis
or THF as solvent was shown to lead to no reaction stereochemistry and (2S,3R) absolute configuration of
and recovery of the starting alcohol (entries 3, 6 and cis-(À)-1h was determined by X-ray crystallogra-
7). Similarly, a survey of other Lewis and Brønsted phy.[13] Experiments showed that in the presence of
acid catalysts did not give improved results with 5 mol% of Cu
ACHTUNGRTENN(UNG OTf)2 as catalyst, starting alcohols cis-
either lower product yields or no reaction found (en- (À)-1b–h and cis-(+)-1i, j efficiently underwent the
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Copper(II) Triflate-Catalyzed Intramolecular Hydroamination of Homoallylic Amino Alcohols
Table 2. Intramolecular hydroamination of 1b–j catalyzed by CuACHTNUTGRNEUNG
(OTf)2.[a]
Substrate
Product
2b, R=Me, (79, >99:1, 97)
1b, R=Me, 99% ee
1c, R=Ph, 7:1 dr, 98% ee
2c, R=Ph, (83, >99:1, 96)
1d, R=Me, 98% ee
1e, R=Et, 98% ee
1f, R=n-Pr, 98% ee
1g, R=Bn, 97% ee
1h, R=Ph, 94% ee
2d, R=Me, (60, >13:1, 96)
2e, R=Et, (56, >15:1, 97)
2f, R=n-Pr, (52, >20:1, 93)
2g, R=Bn, (71, >99:1, 91)
2h, R=Ph, (65,>99:1, 93)
1i, R=i-Pr, 91% ee
1j, R=Bn, 96% ee
2i, R=i-Pr, (72, >20:1, 91)
2j, R=Bn, (72, >99:1, 96)
[a]
All reactions were performed at 808C in (CH2Cl)2 for 15 h with 1:CuCAHTUNGTREN(UGNN OTf)2 ratio=20:1 and values in parenthesis repre-
1
sent isolated yield (%), dr and ee (%) of product. Measurement of trans product dr and ee values based on H NMR and
chiral HPLC analysis.
intramolecular hydroamination process and gave the less effective for the reaction of 1a (entries 18 and 19
corresponding products trans-(+)-2b–h and trans-(À)- in Table 1).
2i, j in good to excellent yields. In these reactions, the
2,5-dihydro-1H-pyrrole adducts were also obtained
with trans selectivities up to >99:1 dr and ee values
of 91–97% that were comparable to those of the re-
Table 3. Intramolecular hydroamination of 3a catalyzed by a
variety of Lewis and Brønsted acids.[a]
spective substrates and consistent with our earlier
findings for cis-(À)-1a. The structure and trans stereo-
chemistry of trans-(+)-2c and trans-(+)-2g were deter-
mined by X-ray crystallographic analysis, with the ab-
solute configuration being (2S,5S).[13] Similarly, the
structure and trans stereochemistry of trans-(À)-2j
Entry
Catalyst
Solvent
Yield [%][b]
were confirmed by X-ray crystallography, with the ab-
solute configuration being (2R,5R).[13]
4a
5
We next sought to assess the scope of this new
methodology and with this mind, first tested the reac-
tion of 3a (Table 3). This led us to find the cyclization
process to proceed well on applying the standard con-
1
Cu
Cu
Cu
Cu
Cu
N
G
97
97
93
78
64
–
–
–
–
30
–
–
54
–
–
2[c]
3
4
5
6
7
8
9
10
11
12
13
ditions with 5 mol% of CuACTHNUTRGNE(UNG OTf)2 as catalyst, giving 4a
[d]
CuOTf
CuI
AgOTf
AuCl/AgOTf
Yb
FeCl3
FeCl3·6H2O
TfOH
–
–
–
in 97% yield (entry 1). Moreover, the same product
yield could be reproduced when the reaction was re-
peated without the exclusion of air and moisture
(entry 2). On the other hand and consistent with our
earlier findings for cis-(À)-1a, reactions of 3a with
other solvents and Lewis and Brønsted acids were
found to lead to lower yields and/or formation of the
diene side product 5 (entries 3–13). Interestingly,
while FeCl3 and TfOH were among the catalysts ex-
amined that resulted in lower products yields (en-
tries 11–13), their ability to effect cyclization is none-
theless noteworthy given that intramolecular hydro-
[d]
[d]
89
(OTf)3
16[e]
80
–
–
–
80
83
[a]
All reactions were performed at 808C for 15 h with 1:cat-
alyst ratio=20:1.
Isolated yield.
Reaction conducted under atmospheric conditions.
No reaction based on TLC and 1H NMR analysis and
near quantitative recovery of the starting alcohol or 43%
yield in the case of AgOTf.
[b]
[c]
[d]
ACHTUNGTRENNUNGaminations mediated by such Lewis and Brønsted
acids have remained sparse.[4,7] In addition, our earlier
results revealed the same catalysts to be markedly
[e]
Starting material was also recovered in 56% yield.
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Table 4. Intramolecular hydroamination of 3b–p catalyzed by CuACHTNUTGRNEUNG
(OTf)2.[a]
Substrate
Product
4b, R=Me, (93)
3b, R=Me
3c, R=OMe
3d, R=Br
4c, R=OMe, (87)
4d, R=Br, (75)
3e, R1 =Me, R2 =H
3f, R1 =H, R2 =OMe
4e, R1 =Me, R2 =H, (98)
3f, R1 =H, R2 =OMe (75)
3g, R=Me
3h, R=Cl
3i, R=Br
4g, R=Me, (97)
4h, R=Cl, (91)
4i, R=Br, (95)
3j, R1 =Me, R2 =H
4j, R1 =Me, R2 =H, (93)
3k, R1 =c-Pr, R2 =Me
4k, R1 =c-Pr, R2 =Me, (79)
1
2
1
2
ꢀ
ꢀ
3l, R =C CPh, R =Me
4l, R =C CPh, R =Me, (84)
3m
4m, (71)
3n
3o
3p
4n, (99)
4o, (94)
4p, (89)
[a]
All reactions were performed at 808C in (CH2Cl)2 for 2-15 h under atmospheric conditions with 3:CuACHTNUTRGNE(UNG OTf)2 ratio=20:1.
Values in parenthesis represent isolated product yield.[14]
Intramolecular hydroamination of a variety of 1-(2- present CuACTHNUTRGENUG(N OTf)2-catalyzed reactions. Indeed, this is
(tosylamino)phenyl)but-3-en-1-ols 3b–p was also further supported by the fact that 4a could be ob-
found to proceed smoothly under these slightly modi- tained in 99% yield when a 1,2-dichloroethane solu-
fied conditions (Table 4). With 5 mol% of Cu
ACHTUNGTRENNUNG
as catalyst, these reactions gave the corresponding CuAHCTUNGTRENNUNG
1,2-dihydroquinolines 4b–p in excellent yields. This in- Scheme 2.
cluded one example of a fused tetracycle (4m). In
these reactions, the structure of 4c was also confirmed
by X-ray crystallographic analysis[13] and no other by-
1
products were detected by H NMR analysis of the
crude mixtures.
The competitive formation of the diene side prod-
uct 5 for the cyclizations of 3a under certain condi-
tions mentioned earlier in Table 3 led us to speculate
on its possible involvement as intermediate in the catalyzed by Cu
AHCTUNGTRENNUNG
Scheme 2. Intramolecular hydroamination of aminodiene 5
(OTf)2.
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Copper(II) Triflate-Catalyzed Intramolecular Hydroamination of Homoallylic Amino Alcohols
It is worth noting that the fact that the trans isomer the starting alcohol nor any of the putative intermedi-
of 5 can also undergo intramolecular hydroamination ates are prone to racemization. This consequently
additionally suggests a reaction involving an inter- allows efficient transfer of the retained chirality at the
mediate that contains an allylbenzylic carbocation a-carbon centre to the amino group and the high
À
moiety. This is evident in a number of control experi- enantioselectivities observed at the newly formed C
ments examined in this work that supports the coop- N bond.
erative involvement of the Brønsted acid with
CuACHTUNGTRENNUNG(OTf)2 in the catalytic cycle. First is the ability of
TfOH to cyclize both 1a and 3a albeit less efficiently. Conclusions
Added to this is the near quantitative recovery of 1a
in reactions with less acidic Cu(I) and Cu(II) salts or In summary, an efficient synthetic strategy for the in-
polar aprotic solvents such as THF and MeCN or in tramolecular hydroamination of aminodienes generat-
the presence of 10 mol% K2CO3 and lower product ed in situ from easily accessible homoallylic alcohols
yields obtained with other metal triflates shown in in the presence of an ecologically benign and low cost
Table 1.
copper catalyst has been reported. This provided a
On the basis of the above results, we tentatively practical and operationally simplistic route to enantio-
propose the mechanism outlined in Scheme 3 for the pure trans-2,5-dihydro-1H-pyrroles with high ee
reaction of cis-(À)-1a, although it is highly specula- values that relied on chirality transfer from enan-
tive. This could involve activation of the alcohol sub- tioenriched substrates as well as 1,2-dihydroquinolines
strate through coordination of the catalyst with the under mild conditions. In the latter case, this included
OH group that results in its elimination and forma- conditions that did not need the exclusion of air or
tion of the aminodiene A. Further coordination of moisture. Our studies revealed that TfOH can also
this newly formed adduct to Cu
(OTf)2, re-generated catalyze the intramolecular hydroamination process.
À
from [Cu] OH by protonolysis, gives Cu(II)-activated However, the lower product yields and selectivities
aminodiene species B. The released TfOH leads to exhibited by the Brønsted acid along with the milder
protonation of the diene moiety of B and formation conditions of copper catalysis provide an attractive al-
of resonance stabilized allylic cation C that is fuÀrther ternative synthetic approach for the formation of
stabilized through ion pairing with the resultant OTf these nitrogen heterocycles.
anion formed. This is the active species that under-
goes the intramolecular hydroamination process to
afford the trans-(+)-2a.[15] The origin of the trans se-
Experimental Section
lectivity could be due carbocationic species adopting
the conformer shown in Scheme 3 so that the poten-
tial for A1,3 strain between the substitutents in allylic
cation C can be kept to a minimum. In this manner,
this would also allow the possibility of unfavourable
transannular strain between the i-Pr and Me groups
to be avoided upon cyclization. The comparable sub-
strate and product ee values also suggest that neither
Representative Experimental Procedure for
CuACTHUNTRGENNG(U OTf)2-Catalyzed Intramolecular Hydroamination
of Enantioenriched 1-(Tosylamino)pent-4-en-2-ols
(1a–1j)
To a solution of the enantioenriched 1-(tosylamino)pent-4-
en-2-ol 1 (0.3 mmol) in 1,2-dichloroethane (3 mL) was
Scheme 3. Tentative mechanism for intramolecular hydroamination of 1a catalyzed by CuACHTUNRGTNEUNG(OTf)2.
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Weidong Rao et al.
FULL PAPERS
added Cu
(OTf)2 (15 mmol) under an argon atmosphere. The
0.5 mLminÀ1): tR (minor)=19.0 min, tR (major)=20.7 min;
96% ee; [a]25: +304.08 (c 1.0, CHCl3).
reaction mixture was stirred at 808C and monitored to com-
pletion by TLC analysis. The reaction mixture was then
cooled to room temperature and the solvent was removed
under reduced pressure. Purification by flash column chro-
matography on silica gel (n-hexane/EtOAc=9:1 as eluent)
gave the product 2.
AHCTUNGTERNNUNG
(2S,5S)-2,D5-Dimethyl-3-phenyl-1-tosyl-2,5-dihydro-1H-pyr-
1
role (2d): Brown oil; H NMR (CDCl3, 400 MHz): d (major
isomer)=1.43 (d, 3H, J=6.3 Hz), 1.45 (d, 3H, J=6.4 Hz),
2.41 (s, 3H), 4.70–4.76 (m, 1H), 5.15–5.21 (m, 1H), 5.80 (s,
1H), 7.26–7.36 (m, 7H), 7.80 (d, 2H, J=8.3 Hz); d (minor
isomer)=1.48–1.51ACTHNUTRGNEUNG(m, 6H), 2.38 (s, 3H), 4.54–4.57 (m, 1H),
4.89–4.94 (m, 1H), 5.77 (s, 1H), 7.75 (d, 2H, J=8.2 Hz);
13C NMR (CDCl3, 100 MHz): d=20.7, 21.5, 21.5, 62.2, 63.6,
125.4, 126.3, 127.0, 128.2, 128.7, 129.5, 132.9, 139.5, 141.7,
142.8; IR (NaCl, neat): v=2971, 1598, 1493, 1335, 1154,
815 cmÀ1; MS (ESI): m/z=328 [M+H]+; HR-MS (ESI):
m/z=328.1377, calcd. for C19H22NO2S (M+ +H): 328.1371;
HPLC (Chiralcel OJ-H, 5% i-PrOH/n-hexanes, 1 mLminÀ1):
tR (minor)=58.4 min, tR (major)=81.9 min; 96% ee; [a]2D5:
+65.68 (c 1.0, CHCl3).
Representative Experimental Procedure for
CuACHTUNGTRENNUNG(OTf)2-Catalyzed Intramolecular Hydroamination
of 1-[2-(Tosylamino)phenyl]but-3-en-1-ols (3a–3p)
To a solution of 1-[2-(tosylamino)phenyl]but-3-en-1-ol 3
(0.3 mmol) in 1,2-dichloroethane (3 mL) was added
CuACHTUNGTRENNUNG(OTf)2 (15 mmol) under atmospheric conditions. The re-
action mixture was stirred at 808C and monitored to com-
pletion by TLC analysis. The reaction mixture then cooled
and the solvent was removed under reduced pressure. Purifi-
cation by flash column chromatography on silica gel (n-
hexane/EtOAc=7:1 as eluent) gave the product 4.
AHCTUNGERTG(NNUN 2S,5S)-2-Ethyl-5-methyl-3-phenyl-1-tosyl-2,5-dihydro-1H-
pyrrole (2e): Brown oil; 1H NMR (CDCl3, 300 MHz): d
(major isomer)=0.55 (t, 3H, J=7.3 Hz), 1.43 (d, 3H, J=
6.4 Hz), 1.55–1.65 (m, 1H), 2.30–2.38 (m, 1H), 2.41 (s, 3H),
4.69–4.76 (m, 1H), 5.27 (s, 1H), 5.86 (s, 1H), 7.26–7.75 (m,
7H), 7.79 (d, 2H, J=8.2 Hz); d (minor isomer)=0.83 (t,
3H, J=7.3 Hz), 4.51–4.54 (m, 1H), 5.00 (s, 1H), 5.72 (s,
1H); 13C NMR (CDCl3, 75 MHz): d=6.5, 21.4, 21.5, 24.5,
63.7, 67.9, 126.4, 126.8, 127.0, 128.2, 128.7, 129.5, 133.2,
138.8, 139.6, 142.7; IR (NaCl, neat): v=2970, 1599, 1495,
1338, 1162, 1121, 814, 673 cmÀ1; MS (ESI): m/z=342 [M+
H]+; HR-MS (ESI): m/z=342.1531, calcd. for C20H24NO2S
(M+ +H): 342.1528; HPLC (Chiralcel AD-H, 3% i-PrOH/n-
hexanes, 0.3 mLminÀ1): tR (minor)=50.6 min, tR (major)=
55.0 min; 97% ee; [a]25: +226.08 (c 1.0, CHCl3).
ACHTUNGTRENNUNG(2S,5S)-2-Isopropyl-5-methyl-3-phenyl-1-tosyl-2,5-dihydro-
1
1H-pyrrole (2a): Brown oil; H NMR (CDCl3, 300 MHz): d
(major isomer)=0.63 (d, 3H, J=7.2 Hz), 0.70 (d, 3H, J=
6.8 Hz), 1.42 (d, 3H, J=6.5 Hz), 2.41 (s, 3H), 2.64–2.72 (m,
1H), 4.60–4.68 (m, 1H), 5.24 (s, 1H), 5.71 (s, 1H), 7.27–7.30
(m, 7H), 7.77 (d, 2H, J=8.3 Hz); d (minor isomer)=0.79
(d, 3H, J=7.0 Hz), 1.05 (d, 3H, J=7.0 Hz), 4.91ACTHNUTRGNEUG(N s, 1H),
5.59 (s, 1H); 13C NMR (CDCl3, 75 MHz): d=16.3, 20.2,
20.9, 21.5, 33.3, 63.1, 73.9, 126.7, 126.9, 128.0, 128.5, 129.5,
129.5, 135.7, 139.6, 140.2, 142.7; IR (NaCl, neat): v=2967,
1599, 1495, 1339, 1159, 814, 758 cmÀ1; MS (ESI): m/z=356
[M+H]+; HRMS (ESI): m/z=356.1687, calcd. for
C21H26NO2S (M+ +H): 356.1684; HPLC (Chiralcel OD-H,
3% i-PrOH/n-hexanes, 0.3 mLminÀ1): tR (minor)=32.1 min,
tR (major)=39.7 min; 93% ee; [a]2D5: +226.08 (c 1.0, CHCl3).
AHCTUNGTERNNUNG
(2S,5S)-5-Methyl-3-Dphenyl-2-propyl-1-tosyl-2,5-dihydro-
1
1H-pyrrole (2f): Brown oil; H NMR (CDCl3, 400 MHz): d
(major isomer)=0.61 (t, 3H, J=7.4 Hz), 0.92–1.05 (m, 2H),
1.44 (d, 3H, J=6.4 Hz), 1.52–1.62 (m, 1H), 2.15–2.25 (m,
1H), 2.41 (s, 3H), 4.69–4.75 (m, 1H), 5.25 (s, 1H), 5.82 (s,
1H), 7.26–7.36 (m, 7H), 7.79 (d, 2H, J=8.2 Hz); d (minor
isomer)=0.82 (t, 3H, J=7.4 Hz), 2.37 (s, 3H), 4.52–4.55 (m,
1H), 4.98 (s, 1H), 5.70 (s, 1H); 13C NMR (CDCl3,
100 MHz): d=13.7, 15.6, 21.4, 21.5, 33.9, 63.6, 67.5, 126.3,
126.7, 126.8, 128.2, 128.7, 129.5, 133.2, 139.3, 139.6, 142.7; IR
(NaCl, neat): v=2960, 1599, 1337, 1161 cmÀ1; MS (ESI):
m/z=356 [M+H]+; HR-MS (ESI): m/z=356.1688, calcd.
for C21H26NO2S (M+ +H): 356.1684; HPLC (Chiralcel AD-
H, 3% i-PrOH/n-hexanes, 0.3 mLminÀ1): tR (minor)=
46.5 min, tR (major)=64.5 min; 93% ee; [a]2D5: +240.88 (c
1.0, CHCl3).
ACHTUNGTRENNUNG(2S,5S)-2-Isopropyl-5-methyl-3-p-tolyl-1-tosyl-2,5-dihydro-
1H-pyrrole (2b): Pale-yellow oil; 1H NMR (CDCl3,
400 MHz): d=0.56 (d, 3H, J=7.2 Hz), 0.62 (d, 3H, J=
6.8 Hz), 1.32 (d, 3H, J=6.5 Hz), 2.25 (s, 3H), 2.32 (s, 3H),
2.54–2.61 (m, 1H), 4.51–4.57 (m, 1H), 5.14 (s, 1H), 5.59 (s,
1H), 7.03–7.20 (m, 6H), 7.69 (d, 2H, J=8.3 Hz); 13C NMR
(CDCl3, 100 MHz): d=16.3, 20.2, 20.9, 21.2, 21.5, 33.3, 63.0,
73.8, 126.6, 126.8, 128.7, 129.2, 129.5, 132.7, 137.9, 139.5,
140.2, 142.6; IR (NaCl, neat): v=2967, 1599, 1337, 1159,
818 cmÀ1; MS (ESI): m/z=370 [M+H]+; HR-MS (ESI):
m/z=370.1848, calcd. for C22H28NO2S (M+ +H): 370.1841;
HPLC
(Chiralcel
OD-H,
3%
i-PrOH/n-hexanes,
0.3 mLminÀ1): tR (minor)=26.3 min, tR (major)=28.2 min;
97% ee; [a]2D5: +224.68 (c 1.0, CHCl3).
AHCTUNGTREG(NNUN 2S,5S)-2-Benzyl-5-methyl-3-phenyl-1-tosyl-2,5-dihydro-
ACHTUNGTRENNUNG(2S,5S)-3-(Biphenyl-4-yl)-2-isopropyl-5-methyl-1-tosyl-2,5-
1H-pyrrole (2g): White solid; mp 155–1568C; 1H NMR
(CDCl3, 300 MHz): d=1.16 (d, 3H, J=6.6 Hz), 2.41 (s, 3H),
2.96 (dd, 1H, J=13.7, 2.0 Hz), 3.72 (dd, 1H, J=13.7,
4.8 Hz), 4.00–4.07 (m, 1H), 5.48 (s, 1H), 5.60 (s, 1H), 7.07–
7.18 (m, 5H), 7.25–7.38 (m, 7H), 7.82 (d, 2H, J=8.3 Hz);
13C NMR (CDCl3, 75 MHz): d=19.7, 21.5, 39.0, 63.5, 68.4,
126.3, 126.4, 126.6, 127.5, 127.7, 128.3, 128.9, 129.6, 130.9,
133.1, 136.3, 138.5, 140.7, 142.8; IR (NaCl, neat): v=3026,
1601, 1495, 1452, 1339, 1157, 1111, 1076, 818 cmÀ1; MS
(ESI): m/z=404 [M+H]+; HR-MS (ESI): m/z=404.1678,
calcd. for C25H26NO2S (M+ +H): 404.1684; HPLC: (Chiral-
cel OD-H, 3% i-PrOH/n-hexanes, 0.3 mLminÀ1): tR
dihydro-1H-pyrrole(2c): Gray solid; mp 160–1618C;
1H NMR (CDCl3, 400 MHz): d=0.71 (d, 3H, J=7.2 Hz),
0.75 (d, 3H, J=6.8 Hz), 1.44 (d, 3H, J=6.5 Hz), 2.42 (s,
3H), 2.67–2.74 (m, 1H), 4.64–4.70 (m, 1H), 5.29 (dd, 1H,
J=2.9, 4.3 Hz), 5.78 (s, 1H), 7.29–7.47 (m, 7H), 7.56–7.61
(m, 4H), 7.80 (d, 2H, J=8.2 Hz); 13C NMR (CDCl3,
100 MHz): d=16.4, 20.3, 20.9, 21.5, 33.4, 63.1, 73.8, 126.7,
127.0, 127.1, 127.3, 127.5, 128.9, 129.5, 134.5, 139.2, 140.1,
140.4, 140.8, 142.7; IR (NaCl, neat): v=2970, 1599, 1487,
1337, 1159, 1061, 670 cmÀ1; MS (ESI): m/z=432 [M+H]+;
HR-MS (ESI): m/z=432.1979, calcd. for C22H28NO2S (M+ +
H): 370.1841; HPLC:(Chiralcel OD, 3% i-PrOH/n-hexanes,
2526
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ꢀ 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Adv. Synth. Catal. 2010, 352, 2521 – 2530

Copper(II) Triflate-Catalyzed Intramolecular Hydroamination of Homoallylic Amino Alcohols
(minor)=36.9 min, tR (major)=44.9 min; 91% ee; [a]2D5:
+317.58 (c 1.0, CHCl3).
50.7, 126.2, 127.5, 127.5, 128.0, 128.6, 128.7, 129.0, 129.6,
130.4, 135.9, 136.3, 136.5, 138.4, 143.2; IR (NaCl, neat): v=
3021, 1485, 1342, 1167, 1038, 885 cmÀ1; MS (ESI): m/z=390
[M+1]+; HR-MS (ESI): m/z=390.1521, calcd. for
C24H24NO2S (M+ +H): 390.1528.
ACHTUNGTRENNUNG(2S,5S)-5-Methyl-2,3-diphenyl-1-tosyl-2,5-dihydro-1H-pyr-
role (2h): Gray solid; mp 123–1248C; 1H NMR (CDCl3,
300 MHz): d=1.71 (d, 3H, J=6.3 Hz), 2.30 (s, 3H), 4.72–
4.79 (m, 1H), 6.07 (d, 1H, J=4.3 Hz), 6.14
(s, 1H), 6.91–7.23
6-Methoxy-2-methyl-4-phenyl-1-tosyl-1,2-dihydroquino-
line (4c): Reaction time=3 h; white solid; mp 146–1478C;
1H NMR (CDCl3, 300 MHz): d=1.12 (d, 3H, J=6.9 Hz),
2.27 (s, 3H), 3.69 (s, 3H), 5.03–5.12 (m, 1H), 5.61 (d, 1H,
J=5.9 Hz), 6.38 (d, 1H, J=2.9 Hz), 6.69–6.72 (m, 2H), 6.88
(dd, 1H, J=8.8, 2.9 Hz),7.02 (d, 2H, J=8.0 Hz), 7.73 (d,
1H, J=8.8 Hz); 13C NMR (CDCl3, 75 MHz): d=19.2, 21.4,
50.8, 55.4, 111.5, 113.0, 125.8, 127.6, 128.0, 128.1, 128.6,
129.1, 130.1, 131.0, 135.8, 136.4, 138.1, 143.2, 157.9; IR
(NaCl, neat): v=3019, 1485, 1341, 1092 cmÀ1; MS (ESI):
m/z=428 [M+Na]+; HR-MS (ESI): m/z=428.1288, calcd.
for C24H23NO3SNa (M+ +Na): 428.1296.
6-Bromo-2-methyl-4-phenyl-1-tosyl-1,2-dihydroquinoline
(4d): Reaction time=4 h; white solid; mp 143–1458C;
1H NMR (CDCl3, 500 MHz): d=1.19 (d, 3H, J=6.9 Hz),
2.29 (s, 3H), 5.06–5.15 (m, 1H), 5.65 (d, 1H, J=6.0 Hz),
6.69–6.72 (m, 2H), 6.98 (d, 1H, J=2.3 Hz), 7.06 (d, 2H, J=
8.1 Hz), 7.23–7.33 (m, 5H), 7.45 (dd, 1H, J=2.3, 8.6 Hz),
7.69 (d, 1H, J=8.6 Hz); 13C NMR (CDCl3, 125 MHz): d=
19.3, 21.4, 50.8, 120.2, 127.4, 127.9, 128.2, 128.5, 128.8, 129.2,
130.4, 131.1, 131.6, 132.1, 135.6, 135.7, 137.4, 143.6; IR
(NaCl, neat): v=3019, 1474, 1339, 1167, 808 cmÀ1; MS
(ESI): m/z=454 [M+1]+; HR-MS (ESI): m/z=454.0492,
calcd. for C23H21NO2SBr (M+ +H): 454.0476.
(m, 14H); 13C NMR (CDCl3, 75 MHz): d=21.4, 22.7, 62.4,
71.7, 126.3, 126.6, 126.9, 127.9, 128.0, 128.2, 128.4, 128.8,
129.2, 132.3, 137.5, 137.7, 139.7, 141.9; IR (NaCl, neat): v=
3023, 2958, 1600, 1340, 1150 cmÀ1; MS (ESI): m/z=390 [M+
H]+; HRMS (ESI): m/z=390.1515, calcd. for C24H24NO2S
(M+ +H): 390.1528; HPLC (Chiralcel OJ-H, 5% i-PrOH/n-
hexanes, 1 mLminÀ1): tR (minor)=38.2 min, tR (major)=
48.5 min; 93% ee; [a]2D5: +58.88 (c 1.0, CHCl3).
ACHTUNGTRENNUNG(2R,5R)-2-Isopropyl-5-methyl-3-phenyl-1-tosyl-2,5-dihy-
1
dro-1H-pyrrole (2i): Brown oil; H NMR (CDCl3, 400 MHz):
d(major isomer)=0.63 (d, 3H, J=7.2 Hz), 0.70 (d, 3H, J=
6.8 Hz), 1.42 (d, 3H, J=6.5 Hz), 2.41 (s, 3H), 2.66–2.71 (m,
1H), 4.61–4.67 (m, 1H), 5.24 (s, 1H), 5.71 (s, 1H), 7.27–7.32
(m, 7H), 7.77 (d, 2H, J=8.3 Hz); d(minor isomer)=0.79 (d,
3H, J=7.0 Hz), 1.05 (d, 3H, J=7.0 Hz), 4.50–4.52 (m, 1H),
4.92 (s, 1H), 5.59 (s, 1H); 13C NMR (CDCl3, 100 MHz): d=
16.3, 20.2, 20.9, 21.5, 33.3, 63.0, 73.8, 126.6, 126.9, 128.0,
128.5, 129.5, 129.5, 135.6, 139.6, 140.1, 142.6; IR (NaCl,
neat): v=2970, 1599, 1495, 1337, 1159, 814, 756 cmÀ1; MS
(ESI): m/z=356 [M+H]+; HR-MS (ESI): m/z=356.1672,
calcd. for C21H26NO2S (M+ +H): 356.1684; HPLC (Chiralcel
OD-H, 3% i-PrOH/n-hexanes, 0.3 mLminÀ1): tR (minor)=
31.9 min, tR (major)=40.1 min; 91% ee; [a]2D5: À217.98 (c 1.0,
CHCl3).
2,7-Dimethyl-4-phenyl-1-tosyl-1,2-dihydroquinoline (4e):
1
(2R,5R)-2-Benzyl-5-methyl-3-phenyl-1-tosyl-2,5-dihydro-
Reaction time=3 h; white solid; mp 139–1408C; H NMR
1H-pyrrole (2j): White solid; mp 155–1568C; 1H NMR
(CDCl3, 400 MHz): d=1.16 (d, 3H, J=6.6 Hz), 2.41 (s, 3H),
2.96 (dd, 1H, J=13.7, 2.0 Hz), 3.72 (dd, 1H, J=13.7,
4.8 Hz), 4.00–4.06 (m, 1H), 5.48 (s, 1H), 5.60 (s, 1H), 7.08–
7.17 (m, 5H), 7.25–7.40 (m, 7H), 7.82 (d, 2H, J=8.3 Hz);
13C NMR (CDCl3, 100 MHz): d=19.7, 21.5, 39.0, 63.5, 68.4,
126.3, 126.4, 126.6, 127.5, 127.7, 128.3, 128.9, 129.6, 130.9,
133.1, 136.3, 138.5, 140.7, 142.8; MS (ESI): m/z=403 [M+
H]+; HR-MS (ESI): m/z=404.1679, calcd. for C25H26NO2S
(M+ +H): 404.1684; HPLC (Chiralcel OD-H, 3% i-PrOH/n-
hexanes, 0.3 mLminÀ1): tR (minor)=37.1 min, tR (major)=
46.9 min; 96% ee; [a]2D5: À345.38 (c 1.0, CHCl3).
(CDCl3, 500 MHz): d=1.19 (d, 3H, J=6.9 Hz), 2.26 (s, 3H),
2.41 (s, 3H), 5.04–5.11 (m, 1H), 5.54 (d, 1H, J=6.0 Hz),
6.71–6.75 (m, 3H), 6.93 (d, 1H, J=7.8 Hz), 7.01 (d, 1H, J=
8.0 Hz), 7.20–7.31 (m, 5H), 7.63 (s, 1H); 13C NMR (CDCl3,
125 MHz): d=19.3, 21.4, 21.5, 50.8, 125.6, 126.3, 127.2,
127.3, 127.5, 127.5, 127.9, 128.6, 129.0, 129.3, 132.9, 135.9,
136.3, 138.4, 143.2; IR (NaCl, neat): v=3024, 1493, 1445,
1344, 1167, 1090 cmÀ1; MS (ESI): m/z=390 [M+1]+; HR-
MS (ESI): m/z=390.1523, calcd. for C24H24NO2S (M+ +H):
390.1528.
8-Methoxy-2-methyl-4-phenyl-1-tosyl-1,2-dihydroquino-
line (4f): Reaction time=4 h; white solid; mp 165–1678C;
1H NMR (CDCl3, 400 MHz): d=1.17 (d, 3H, J=6.9 Hz),
2.26 (s, 3H), 3.95 (s, 3H), 4.90–4.97 (m, 1H), 5.60 (d, 1H,
J=5.8 Hz), 6.55 (d, 1H, J=7.7 Hz), 6.85–6.88 (m, 2H), 6.99
(d, 1H, J=8.3 Hz), 7.07–7.14 (m, 3H), 7.23–7.26 (m, 3H),
7.48 (d, 1H, J=8.2 Hz); 13C NMR (CDCl3, 100 MHz): d=
18.1, 21.4, 51.0, 56.5, 113.1, 118.2, 121.9, 127.5, 127.5, 127.9,
127.9, 128.7, 129.0, 129.1, 132.0, 136.7, 136.8, 138.1, 143.1,
157.5; IR (NaCl, neat): v= 3019, 1574, 1476, 1271, 1165,
1076, 795 cmÀ1; MS (ESI): m/z=428 [M+Na]+; HR-MS
(ESI): m/z=428.1280, calcd. for C24H23NO3SNa (M+ +Na):
428.1296.
2-Methyl-4-phenyl-1-tosyl-1,2-dihydroquinoline (4a): Re-
action time=15 h; white solid; mp 162–1638C; 1H NMR
(CDCl3, 500 MHz): d=1.20 (d, 3H, J=6.9 Hz), 2.27 (s, 3H),
5.08–5.14 (m, 1H), 5.62 (d, 1H, J=6.0 Hz), 6.72 (d, 2H, J=
5.9 Hz), 6.86 (d, 1H, J=7.7 Hz), 7.02 (d, 2H, J=8.0 Hz),
7.12 (t, 1H, J=7.5 Hz), 7.23–7.34 (m, 6H), 7.81 (d, 1H, J=
8.0 Hz); 13C NMR (CDCl3, 125 MHz): d=19.3, 21.4, 50.8,
125.8, 126.5, 127.5, 127.5, 128.0, 128.2, 128.8, 129.0, 129.9,
133.0, 135.9, 136.4, 138.2, 143.3; IR (NaCl, neat): v=3018,
1477, 1341, 1084, 813 cmÀ1; MS (ESI): m/z=398 [M+Na]+;
HR-MS (ESI): m/z=398.1192, calcd. for C23H21NO2SNa
(M+ +Na): 398.1191.
2-Methyl-4-p-tolyl-1-tosyl-1,2-dihydroquinoline (4g): Re-
action time=3 h; white solid; mp 149–1508C; 1H NMR
(CDCl3, 400 MHz): d=1.19 (d, 3H, J=6.9 Hz), 2.27 (s, 3H),
2.34 (s, 3H), 5.06–5.13 (m, 1H), 5.59 (d, 1H, J=6.0 Hz),
6.61 (d, 2H, J=7.9 Hz), 6.86 (d, 1H, J=7.7 Hz), 7.01 (d,
2H, J=8.2 Hz), 7.10–7.13 (m, 5H), 7.25–7.33 (m, 3H), 7.79
(d, 1H, J=8.0 Hz); 13C NMR (CDCl3, 100 MHz): d=19.3,
21.2, 21.4, 50.8, 125.8, 126.4, 127.1, 127.5, 128.1, 128.5, 128.7,
2,6-Dimethyl-4-phenyl-1-tosyl-1,2-dihydroquinoline (4b):
1
Reaction time=6 h; white solid; mp 158–1608C; H NMR
(CDCl3, 300 MHz): d=1.19 (d, 3H, J=6.9 Hz), 2.23 (s, 3H),
2.27 (s, 3H), 5.03–5.11 (m, 1H), 5.68 (d, 1H, J=6.0 Hz),
6.64 (s, 1H), 6.71–6.74 (m, 2H), 7.02 (d, 2H, J=8.1 Hz),
7.14 (d, 1H, J=6.8 Hz), 7.15–7.32 (m, 5H), 7.68 (d, 1H, J=
8.1 Hz); 13C NMR (CDCl3, 75 MHz): d=19.2, 21.2, 21.4,
Adv. Synth. Catal. 2010, 352, 2521 – 2530
ꢀ 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
asc.wiley-vch.de
2527

Weidong Rao et al.
FULL PAPERS
128.8, 129.0, 130.0, 133.0, 135.3, 135.9, 136.3, 137.3, 143.3; IR
(NaCl, neat): v= 3021, 1344, 1167, 1091 cmÀ1; MS (ESI):
m/z=390 [M+1]+; HR-MS (ESI): m/z=390.1527, calcd. for
C24H24NO2S (M+ +H): 390.1528.
MS (ESI): m/z=436.1345, calcd. for C26H23NO2SNa (M+ +
Na): 436.1347.
2-Methyl-3-tosyl-2,3-dihydroindenoACHTUNGTERN[UNNG 1,2,3-de]quinoline
1
(4m): Reaction time=3 h; pale-yellow oil; H NMR (CDCl3,
400 MHz): d=1.44 (d, 3H, J=6.8 Hz), 2.23 (s, 3H), 5.33–
5.39 (m, 1H), 6.29 (d, 1H, J=5.0 Hz), 7.02 (d, 2H, J=
8.0 Hz), 7.26–7.45 (m, 6H), 7.55 (d, 1H, J=7.5 Hz), 7.68–
7.71 (m, 2H); 13C NMR (CDCl3, 100 MHz): d=21.4, 23.1,
54.9, 116.7, 120.9, 122.0, 122.5, 126.7, 127.1, 128.2, 128.7,
129.4, 129.7, 131.4, 132.2, 135.4, 136.1, 137.0, 141.2, 143.6; IR
(NaCl, neat): v=3022, 1612, 1595, 1445, 1437, 1163,
812 cmÀ1; MS (ESI): m/z=374 [M+1]+; HR-MS (ESI):
m/z=374.1183, calcd. for C23H20NO2S (M+ +H): 374.1215.
2-Methyl-4-phenyl-1-tosyl-1,2-dihydrobenzo[g]quinoline
(4n): Reaction time=4 h; pale-yellow solid, mp 163–1648C;
1H NMR (CDCl3, 400 MHz): d=1.25 (d, 3H, J=6.9 Hz),
2.25 (s, 3H), 5.14–5.21 (m, 1H), 5.76 (1H, J=6.0 Hz), 6.81
(d, 1H, J=5.8 Hz), 6.98 (d, 1H, J=8.2 Hz), 7.27–7.49 (m,
8H), 7.60 (d, 1H, J=8.1 Hz), 7.90 (d, 1H, J=8.2 Hz), 8.29
(s, 1H); 13C NMR (CDCl3, 100 MHz): d=19.9, 21.4, 51.0,
126.1, 126.3, 126.6, 127.4, 127.5, 127.7, 128.0, 128.0, 128.1,
128.8, 129.1, 129.2, 130.9, 131.8, 133.0, 136.1, 136.8, 138.5,
143.3; IR (NaCl, neat): v= 3019, 1493, 1346, 1167, 1094,
1028, 903 cmÀ1; MS (ESI): m/z=426 [M+1]+; HR-MS
(ESI): m/z=426.1531, calcd. for C27H24NO2S (M+ +H):
426.1528.
4-(4-Chlorophenyl)-2-methyl-1-tosyl-1,2-dihydroquinoline
(4h): Reaction time=5 h; white solid; mp 172–1738C;
1H NMR (CDCl3, 400 MHz): d=1.19 (d, 3H, J=6.9 Hz),
2.28 (s, 3H), 5.57–5.14 (m, 1H), 5.61 (d, 1H, J=6.0 Hz),
6.66 (d, 2H, J=8.3 Hz), 6.81 (d, 1H, J=7.8 Hz), 7.02 (d,
2H, J=8.2 Hz), 7.12–7.37 (m, 6H), 7.81 (d, 1H, J=8.0 Hz);
13C NMR (CDCl3, 125 MHz): d=19.2, 21.4, 50.7, 125.5,
126.6, 127.5, 127.9, 128.2, 128.5, 129.0, 129.0, 129.5, 129.9,
133.0, 133.5, 135.4, 135.8, 136.7, 143.3; IR (NaCl, neat): v=
3022, 1344, 1165, 1088 cmÀ1; MS (ESI): m/z=410 [M+1]+;
HR-MS (ESI): m/z=410.0995, calcd. for C23H21NO2SCl
(M+ +H): 410.0982.
4-(4-Bromophenyl)-2-methyl-1-tosyl-1,2-dihydroquinoline
(4i): Reaction time=3 h; white solid; mp 164–1658C;
1H NMR (CDCl3, 400 MHz): d=1.19 (d, 3H, J=6.9 Hz),
2.28 (s, 3H), 5.07–5.14 (m, 1H), 5.62 (d, 2H, J=6.0 Hz),
6.60 (d, 2H, J=8.3 Hz), 6.82 (d, 1H, J=7.7 Hz), 7.02 (d,
2H, J=8.2 Hz), 7.13 (t, 1H, J=7.5 Hz), 7.26–7.38 (m, 5H),
7.81 (d, 1H, J=8.0 Hz); 13C NMR (CDCl3, 100 MHz): d=
19.2, 21.4, 50.7, 121.6, 125.5, 126.6, 127.5, 127.9, 128.5, 129.0,
129.0, 129.4, 130.3, 131.2, 133.0, 135.4, 135.8, 137.2, 143.3; IR
(NaCl, neat): v=3019, 1485, 1341, 814 cmÀ1; MS (ESI):
m/z=454 [M+1]+; HR-MS (ESI): m/z=454.0494, calcd. for
C23H21NO2SBr (M+ +H): 454.0476.
2,2-Dimethyl-4-phenyl-1-tosyl-1,2-dihydroquinoline (4o):
Reaction time=4 h; white solid, mp 159–1608C; 1H NMR
(CDCl3, 500 MHz): d=1.56 (s, 6H), 2.24 (s, 3H), 5.46 (s,
1H), 6.86–6.87 (m, 2H), 6.95 (d, 1H, J=7.6 Hz), 7.02 (d,
2H, J=8.0 Hz), 7.16–7.37 (m, 7H), 7.78 (d, 1H, J=8.0 Hz);
13C NMR (CDCl3, 125 MHz): d=21.4, 28.2, 58.2, 125.4,
126.6, 127.6, 127.7, 127.9, 128.0, 128.7, 129.1, 130.6, 130.9,
133.5, 136.7, 136.9, 137.7, 137.8, 142.9; IR (NaCl, neat): v=
3021, 1599, 1348, 1159, 1090, 984 cmÀ1; MS (ESI): m/z=390
[M+1]+; HR-MS (ESI): m/z=390.1529, calcd. for
C24H24NO2S (M+ +H): 390.1528.
2-Phenethyl-4-phenyl-1-tosyl-1,2-dihydroquinoline (4p):
Reaction time=2 h; white solid, mp 155–1568C; 1H NMR
(CDCl3, 400 MHz): d=1.67–1.82 (m, 2H), 2.26 (s, 3H),
2.74–2.82 (m, 1H), 2.86–2.93 (m, 1H), 4.96–5.01 (m, 1H),
5.69 (d, 1H, J=6.0 Hz), 6.68 (d, 2H, J=7.0 Hz), 6.85 (d,
1H, J=7.7 Hz), 7.00 (d, 2H, J=8.0 Hz), 7.10–7.35 (m,
12H), 7.82 (d, 1H, J=8.0 Hz); 13C NMR (CDCl3, 100 MHz):
d=21.4, 31.7, 34.3, 54.7, 125.9, 125.9, 126.5, 126.6, 127.5,
127.6, 128.0, 128.4, 128.6, 128.6, 128.8, 129.1, 130.2, 133.1,
135.9, 137.0, 138.2, 141.6, 143.4; IR (NaCl, neat): v=3022,
1599, 1450, 1072, 812 cmÀ1; MS (ESI): m/z=466 [M+1]+;
HR-MS (ESI): m/z=466.1838, calcd. for C30H28NO2S (M+ +
H): 466.1841.
4-Methyl-N-(2-(1-phenylbuta-1,3-dienyl)phenyl)benzene-
sulfonamide (5): Yellow oil; 1H NMR (CDCl3, 400 MHz):
d=2.34 (s, 3H), 2.37 (s, 3H), 5.10 (d, 1H, J=10.1 Hz), 5.24
(t, 2H, J=8.7 Hz), 5.40 (d, 1H, J=16.8 Hz), 5.80–5.89 (m,
2H), 6.26 (s, 1H), 6.47–5.60 (m, 2H), 6.82 (d, 1H, J=
11.0 Hz), 7.00–7.47 (m, 22H), 7.60 (d, 1H, J=8.2 Hz), 7.76
(d, 2H, J=8.2 Hz); 13C NMR (CDCl3, 100 MHz): d=21.5,
119.8, 120.7, 120.9, 123.0, 124.4, 125.3, 126.3, 127.2, 127.3,
128.2, 128.4, 128.7, 128.9, 129.0, 129.3, 129.4, 129.5, 129.6,
130.8, 130.8, 131.3, 132.6, 133.5, 133.6, 134.3, 134.7, 136.0,
136,0, 136.1, 137.2, 138.1, 138.5, 139.0, 143.6, 143.7; IR
(NaCl, neat): v=3275, 1491, 1452, 911 cmÀ1; MS (ESI):
2,4-Dimethyl-1-tosyl-1,2-dihydroquinoline (4j): Reaction
time=20 h; white solid; mp 68–698C; 1H NMR (CDCl3,
500 MHz): d=1.09 (d, 3H, J=6.9 Hz), 1.58 (s, 3H), 2.32 (s,
3H), 4.81–4.87 (m, 1H), 5.37 (d, 1H, J=5.8 Hz), 7.02–7.32
(m, 7H), 7.72 (d, 1H, J=8.0 Hz); 13C NMR (CDCl3,
125 MHz): d=17.7, 19.6, 21.4, 50.7, 123.1, 126.2, 126.6,
127.3, 127.8, 128.3, 128.8, 128.9, 130.5, 132.7, 135.9, 143.1; IR
(NaCl, neat): v=3012, 1485, 1450, 1344, 1165, 1051 cmÀ1
;
MS (ESI): m/z=336 [M+Na]+; HR-MS (ESI): m/z=
336.1035, calcd. for C18H19NO2SNa (M+ + Na): 336.1034.
4-Cyclopropyl-2,6-dimethyl-1-tosyl-1,2-dihydroquinoline
(4k): Reaction time=6 h; white solid; mp 105–1068C;
1H NMR (CDCl3, 400 MHz): d=À0.44–À0.38 (m, 1H),
0.00–0.07 (m, 1H), 0.40–0.47 (m, 1H), 0.59–0.65 (m, 1H),
1.07 (d, 3H, J=6.8 Hz), 1.21–1.28 (m, 1H), 2.32 (s, 3H),
2.37 (s, 3H), 4.82–4.88 (m, 1H), 5.33 (dd, 1H, J=5.9,
1.5 Hz), 7.03 (d, 2H, J=8.1 Hz), 7.11(dd, 1H, J=8.1,
1.5 Hz), 7.19–7.24 (m, 3H), 7.59 (d, 1H, J=8.1 Hz);
13C NMR (CDCl3, 100 MHz): d=4.1, 5.6, 11.6, 19.6, 21.4,
50.7, 124.1, 124.9, 127.3, 128.1, 128.4, 128.8, 129.8, 130.3,
134.4, 136.1, 136.2, 143.1; IR (NaCl, neat): v=3017, 1487,
1344, 1163, 1094, 1040, 814 cmÀ1; MS (ESI): m/z=376 [M+
Na]+;
C21H23NO2SNa (M+ + Na): 376.1347.
HR-MS
(ESI):
m/z=376.1341,
calcd.
for
2,6-Dimethyl-4-(phenylethynyl)-1-tosyl-1,2-dihydroquino-
1
line (4l): Reaction time=2 h; yellow oil; H NMR (CDCl3,
400 MHz): d=1.16 (d, 3H, J=6.9 Hz), 2.29 (s, 3H), 2.38 (s,
3H), 4.93–5.00 (m, 1H), 5.96 (d, 1H, J=6.0 Hz), 7.10 (d,
2H, J=8.3 Hz), 7.17 (dd, 1H, J=8.2, 1.7 Hz), 7.26–7.45 (m,
8H), 7.61 (d, 1H, J=8.2 Hz); 13C NMR (CDCl3, 100 MHz):
d=19.2, 21.3, 21.5, 50.9, 84.9, 91.2, 118.3, 122.9, 125.8, 127.2,
127.2, 128.0, 128.4, 128.5, 129.2, 129.6, 129.8, 131.5, 134.5,
135.6, 136.6, 143.6; IR (NaCl, neat): v=3021, 1489, 1344,
1159, 1092, 812 cmÀ1; MS (ESI): m/z=436 [M+Na]+; HR-
2528
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ꢀ 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Adv. Synth. Catal. 2010, 352, 2521 – 2530

Copper(II) Triflate-Catalyzed Intramolecular Hydroamination of Homoallylic Amino Alcohols
m/z=376 [M+1]+; HR-MS (ESI): m/z=376.1359, calcd. for
C23H22NO2S (M+ +H): 376.1371.
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and Science and Engineering Research Council Grant (092
101 0053) from A*STAR, Singapore.
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[13] Please refer to Figures S91–S95 in the Supporting In-
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[15] Intermediates similar to those depicted in Scheme 3
have also been proposed in other copper catalyzed hy-
droamination reactions, please refer to ref.[3]
2530
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Adv. Synth. Catal. 2010, 352, 2521 – 2530