Tetrathiomolybdate mediated rearrangement of aziridinemethanol tosylates: A thia-aza-payne rearrangement

Article abstract of DOI:10.1021/jo100640w

Aziridinemethanol sulfonate esters react with tetrathiomolybdate 1 to give thiirane derivatives as the major product and cyclic disulfides as minor product under mild reaction conditions via an unprecedented thia-aza-Payne-type rearrangement. Interestingly, when the reaction of 1 was carried out with 2-aziridino-cyclohexanol derivatives it resulted in the formation of thia-bicyclo[3.1.1]heptane or dithia-bicyclo[3.2.1]octane derivatives.

Full text of DOI:10.1021/jo100640w

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Tetrathiomolybdate Mediated Rearrangement of Aziridinemethanol
Tosylates: A Thia-Aza-Payne Rearrangement
Devarajulu Sureshkumar, Srinivasamurthy Koutha, Venkataraman Ganesh, and
Srinivasan Chandrasekaran*,†,‡
Department of Organic Chemistry, Indian Institute of Science, Bangalore-560012, Karnataka, India.
†Honorary Professor, Jawaharlal Nehru Center for Advanced Scientific Research, Jakkur, Bangalore.
‡Dedicated to Professor Henri Kagan, Universite’ Paris-sud, Orsay, France on the occasion of his 80th birthday
scn@orgchem.iisc.ernet.in
Received April 12, 2010
Aziridinemethanol sulfonate esters react with tetrathiomolybdate 1 to give thiirane derivatives as the
major product and cyclic disulfides as minor product under mild reaction conditions via an
unprecedented thia-aza-Payne-type rearrangement. Interestingly, when the reaction of 1 was carried
out with 2-aziridino-cyclohexanol derivatives it resulted in the formation of thia-bicyclo[3.1.1]heptane or
dithia-bicyclo[3.2.1]octane derivatives.
Introduction
and tellurium nucleophiles7 in the presence of Lewis acid has
been shown to provide allyl amine and allyl alcohol deriva-
tives, respectively. One important aspect of these rearrange-
ments is that the reaction is usually stereospecific, proceeding
with inversion of configuration at the C-2 carbon of the
epoxide ring via SN2-type pathway (Scheme 1). Earlier we
have reported our results on the ring-opening of aziridines
using benzyltriethylammonium tetrathiomolybdate,
[BnEt3N]2MoS4 (1), as a sulfur transfer reagent8 to synthe-
size β-aminosulfides, disulfides,9a functionalized unsymme-
trical disulfides,9b and sulfur heterocycles.10 We have also
reported recently a Selena-aza-Payne-type rearrangement
of aziridinemethanol tosylates using tetraethylammonium
tetraselenotungstate.11
Payne rearrangement of 2,3-epoxy alcohols is a well-
known and widely studied reaction.1,2 Similarly, the aza-
Payne,3 and thia-Payne4 rearrangements of 2,3-epoxy
amines and sulfides are also well studied and have received
much attention.5 The reaction of N-tosyl-2-aziridinemetha-
nol tosylates and 2-epoxymethanol tosylates with selenium6
*Author to whom correspondence should be addressed. Phone: þ91-80-
2293 2404. Fax: þ91-80-2360 2423.
(1) (a) Payne, G. B. J. Org. Chem. 1962, 27, 3819–3822. (b) Sharpless,
K. B.; Behrens, C. H.; Katsuki, T.; Lee, A. W.; Martin, V. S.; Takatani, M.;
Viti, S. M.; Walker, F. J.; Woodard, S. S. Pure Appl. Chem. 1983, 589–604.
(2) (a) Rayner, C. M. Synlett 1997, 11–21. (b) Tamamura, H.; Hori, T;
Otaka, A.; Fujii, N. J. Chem. Soc., Perkin Trans. 2002, 1, 577–580.
(3) Ibuka, T. Chem. Soc. Rev. 1998, 27, 145-154 and references cited
therein.
(4) (a) Branalt, J.; Kvarnstrom, I.; Classon, B.; Samuelsson, B. J. Org.
Chem. 1996, 61, 3604–3610. (b) Gill, D. M.; Pegg, N. A.; Rayner, C. M.
Tetrahedron 1996, 52, 3609–3630. (c) Liu, C. Q.; Hashimoto, U.; Kudo, K.;
Saigo, K. Bull. Chem. Soc. Jpn. 1996, 69, 2095–2105. (d) Sasaki, M.;
Miyazawa, M.; Tanino, K.; Miyashita, M. Tetrahedron Lett. 1999, 40,
9267–9270. (e) Hayakawa, H.; Okada, N.; Miyashita, M. Tetrahedron Lett.
1999, 40, 3191–3194.
(5) Hanson, R. M. In Organic Reactions; Overman, L. E., Ed.; John Wiley
& Sons: New York, 2002; Vol. 60, pp 1-156.
(6) Polson, G.; Dittmer., D. C. J. Org. Chem. 1988, 53, 791–794.
(7) Pepito, A. S.; Dittmer, D. C. J. Org. Chem. 1997, 62, 7920–7925.
(8) Prabhu, K. R.; Devan, N.; Chandrasekaran, S. Synlett 2002, 1762–
1778.
(9) (a) Sureshkumar, D.; Gunasundari, T.; Ganesh, V.; Chandrasekaran,
S. J. Org. Chem. 2007, 72, 2106–2117. (b) Sureshkumar, D.; Ganesh, V.;
Sasitha, R.; Chandrasekaran, S. J. Org. Chem. 2009, 74, 7958–7961.
(10) Sureshkumar, D.; Koutha, S.; Chandrasekaran, S. J. Am. Chem.
Soc. 2005, 127, 12760–12761.
(11) Sureshkumar, D.; Koutha, S.; Chandrasekaran, S. Eur. J. Org.
Chem. 2007, 4543–4551.
DOI: 10.1021/jo100640w
r
Published on Web 07/28/2010
J. Org. Chem. 2010, 75, 5533–5541 5533
2010 American Chemical Society

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SCHEME 1. Different Types of Thia-Payne Rearrangement
SCHEME 3. Regiospecific Ring-Opening of Aziridine Methanol
Tosylate 2a with 1
SCHEME 2. Thia-Aza-Payne-Type Rearrangement of Different
Aziridinemethanol Tosylates
SCHEME 4. Regiospecific Ring-Opening of Disubstituted
Aziridinemethanol Tosylate 2b with 1
In the present article we wish to report a detailed study on
the regio- and stereospecific ring-opening of a number of
aziridinemethanol tosylates 2 with 1 to afford the correspond-
ing thiirane derivatives 3 as the major products and the cyclic-
disulfides 4 as the minor products as shown in Scheme 2.
SCHEME 5. Synthesis of Aziridinemethanol Tosylates 2 from
Allylic Alcohols 9
Results and Discussion
Ring-Opening of Mono- and 2,2-Disubstituted N-Tosyl
Aziridines with 1. Our investigation began with the study of
nucleophilic ring-opening of optically pure N-tosyl-aziridi-
nemethanol tosylate 2a with 1 to obtain the corresponding
optically active thiirane derivative 3a. The aziridinemethanol
tosylate 2a was synthesized in 90% yield from (R)-3-amino-
1,2-propanediol (5), by tosylation with p-toluenesulfonyl
chloride in pyridine followed by cyclization of 6 with potas-
sium carbonate.12 Treatment of 2a with 1 [2.1 equiv, CH3CN,
28 °C, 8 h] failed to furnish the thiirane derivative 3a, but
resulted in a smooth ring-opening at C3 in a regiospecific
manner followed by cyclization to afford meso-cyclic disulfide
derivative 4a as the single product in 80% yield (Scheme 3).
This methodology was then extended to the reaction of
2,2-disubstituted aziridinemethanol tosylate 2b. Compound
2b was synthesized from 2-amino-2-methyl-1,3-propanediol
(7) via the ditosylate 8 as shown in Scheme 4.11 Treatment of
2b with 1 [2.1 equiv, CH3CN, 28 °C, 8 h] furnished the desired
thiirane derivative 3b as the major product and cyclic
disulfide derivative 4b as the minor product (4:1 ratio) in
78% yield. In the course of this thia-aza-Payne-type rear-
rangement to form 3b, nitrogen migration occurs from C3,
C2 to C1 position (Scheme 4).
SCHEME 6. Ring-Opening of Aziridinemethanol Tosylates 2
with Chloride Ion (Cl-)
0.3 mmol; 15 mL of CH3CN, rt, 12 h] followed by tosylation
of aziridinemethanols 10 with p-toluenesulfonyl chloride,
a catalytic amount of DMAP, and pyridine in CH2Cl2 at
-15 °C for 24 h (Scheme 5).
When performing the tosylation of aziridinemethanols 10,
care has to be taken while doing the workup; before quench-
ing the excess pyridine and DMAP with dilute HCl,
the reaction mixture has to be diluted with diethyl ether at
-15 °C. Otherwise, the aziridine tosylate 2 undergoes ring-
opening with chloride ion (Cl-) of pyridinium hydrochloride
to give ring-opened product 20 as shown in Scheme 6.
Ring-Opening of 2,3-Disubstituted N-Tosyl Aziridines with
1. To address the issue of whether the reaction of 1 takes
place at the tosylate first or aziridine ring opens first and
assess the regio- and stereospecificity of aziridine ring-open-
ing, this methodology was then extended to the reaction of
(()-trans-N-tosyl aziridinemethanol tosylate 2c with 1
(2.1 equiv; CH3CN, 28 °C, 6 h). This led to the formation
of trans-thiirane derivative 3c as the major product and
trans-cyclic disulfide derivative 4c as the minor product
General Synthesis of Other Aziridinemethanol Tosylates.
To expand the scope of this methodology, synthesis of a
number of aziridinemethanol tosylates 2 was achieved start-
ing from allylic alcohols 9 using Sharpless’s aziridination
protocol13 [allylic alcohol, 3 mmol; CAT (Chloramine-T),
3.3 mmol; PTAB (phenyltrimethylammonium tribromide),
(12) Axenrod, T.; Watnick, C.; Yazdekhasti, H. J. Org. Chem. 1995, 60,
1959–1964.
(13) Jeong, J. U.; Tao, B.; Sagasser, I.; Henniges, H.; Sharpless, K. B.
J. Am. Chem. Soc. 1998, 120, 6844–6845.
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TABLE 1. Thia-Aza-Payne-Type Rearrangement of Different Aziridinemethanol Tosylates 2d-j
(3:1) in good yield with excellent regio- and stereocontrol
(Table 1, entry 1). The stereochemistry of compounds 3c14
and 4c15 was confirmed by single-crystal X-ray analysis (see
the Supporting Information).
Subsequently, the reaction of 1 with a number of trans-2,3-
disubstituted aziridinemethanol tosylates 2d-f was studied
and in all the cases the reaction proceeded smoothly to give
the corresponding trans-thiirane derivatives 3d-f as the major
products and the cyclic disulfides 4d-f as the minor products
with excellent regio- and stereocontrol (Table 1, entries 2-4).
The reaction of (()-cis-N-tosyl aziridinemethanol tosylate
2g with 1 [2.1 equiv; CH3CN, 28 °C, 12 h] led to the formation
of the cis-thiirane 3g as the major product and cis-cyclic
disulfide 4g as the minor product (4:1) in good yield. Similarly,
2h on treatment with 1 gave 3h and 4h in 4:1 ratio as shown in
Table 1, entries 5 and 6. Interestingly, aziridinemethanol
tosylate 2i failed to undergo the rearrangement, but gave the
cyclic disulfide 4i as the only product in 60% yield (entry 7).16
(14) Thestructurewassolvedbydirectmethods (SIR92). Refinement was by
full-matrix least-squares procedures on F2 by using SHELXL-97. CCDC No.
288573. Crystal system: monoclinic; space group: P21/n; cell parameters: a =
˚
˚
˚
5.169(3) A, b = 29.506(1) A, c = 8.521(5) A, a = 90.00°, b = 100.04(1)°, g =
3
90.00°, V = 1279(3) A , Z = 4, Fcalcd = 1.34 g cm-3, F(000) = 543.9, m = 0.40
˚
mm-1, l = 0.71073 A. Total number l.s. parameters = 145. R1 = 0.057 for 2240
˚
Fo > 4σ(Fo) and 0.09 for all 9066 data. wR2 = 0.153, GOF = 1.000, restrained
GOF = 1.000 for all data.
(15) The structure was solved by direct methods (SIR92). Refinement was
by full-matrix least-squares procedures on F2 by using SHELXL-97. CCDC
No. 288574. Crystal system: monoclinic; space group: P21/n; cell parameters:
˚
˚
˚
a = 12.469(7) A, b = 7.347(4) A, c = 15.965(9) A, a = 90.00°, b =
3
112.404(9)°, g = 90.00°, V = 1352.3(6) A , Z = 4, Fcalcd = 1.42 g cm-3
,
˚
F(000) = 607.9, m = 0.54 mm-1, l = 0.71073 A. Total number l.s.
parameters = 154. R1 = 0.056 for 2370 Fo > 4σ(Fo) and 0.067 for all
9165 data. wR2 = 0.146, GOF = 1.138, restrained GOF = 1.138 for all data.
˚
(16) In the case of 2i the formation of only cis-cyclic disulfide derivative 4i
during the reaction remains to be studied further.
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SCHEME 7. Tentative Mechanism for the Formation of 3c and 4c
The reaction of 2,3,3-trisubstituted aziridinemethanol to-
sylate 2j with 1 (2.1 equiv, CH3CN, 28 °C, 13 h) furnished
thiirane derivative 3j as the major product and the cyclic
disulfide 4j (3:1) as the minor product in good yields (Table 1,
entry 8). The structure of cyclic disulfide 4j17 was confirmed
by single-crystal X-ray analysis (Figure 1).
course of this thia-aza-Payne-type rearrangement to from 3c,
nitrogen migration occurs from C2, C3 to C1 position, with the
formation of thiirane 3c with same stereochemistry. During the
formation of 3c, the reaction tends to follow path a. In path a,
tetrathiomolybdate 1 attacks the aziridine 2c at C3 in an SN2
fashion to give intermediate X1, which can further go through
two different pathways: path a1 and a2. In path a1, intramo-
lecular displacement of the tosyl group by nitrogen nucleophile
would give an aziridine intermediate X2. Ring-opening of the
newly formed aziridine X2 by sulfur nucleophile will give the
thiirane intermediate X3, which after protonation leads to
thiirane derivative 3c with trans stereochemistry. In path a2,
intramolecular displacement of tosylate by sulfur nucleophile
would give a six-membered intermediate X4. This intermediate
can lead to cyclic disulfide 4c (observed experimentally) by an
internal redox process18 with elimination of MoS2/[Mo3S9]2-
as byproducts.
In path b, tetrathiomolybdate 1 attacks the aziridine 2c at
the C1 position in an SN2 fashion to give intermediate Y1,
which can further undergo two types of reactions via either
path b1 or b2. In path b1, nucleophilic ring-opening of aziridine
at C3 with sulfur nucleophile would give six-membered inter-
mediate X4, which undergoes further transformation to give
cyclic disulfide 4c as mentioned in the case of path a2. In path
b2, sulfur nucleophile attacks the aziridine at C2 to give thiirane
intermediate Y2, which undergoes further protonation during
workup to give 1,2-thiirane derivative 3c0 (not observed
experimentally). On the basis of these observations one may
conclude that in the reaction of 2c with 1 the ring-opening of
aziridine takes place first followed by further reaction with the
tosylate to give the observed products.
FIGURE 1. X-ray ORTEP diagram of compound 4j.
Tentative Mechanism for the Thia-Aza-Payne-Type Rear-
rangement. On the basis of the results of this investigation, a
tentative mechanism for the formation of products 3c and 4c is
presented in Scheme 7 and it is analogous to the pathway
suggested earlier in the case of tetraselenotungstate.11 In the
Reaction of Tetrathiomolybdate 1 with Aziridino-Tosylates
Derived from Cyclic-Allylic Alcohols. Finally, this methodol-
(17) Thestructurewassolvedbydirectmethods (SIR92). Refinement was by
full-matrix least-squares procedures on F2 by using SHELXL-97. CCDC No.
648189. Crystal system: triclinic; space group: P1; cell parameters: a = 7.238(4)
˚
˚
˚
A, b = 10.304(5) A, c = 10.950(6) A, a = 109.161(8)°, b = 102.369(8)°, g =
3
94.459(9)°, V = 743.8(3) A , Z = 2, Fcalcd = 1.35 g cm-3, F(000) = 320, m =
˚
0.49 mm-1, l = 0.71073 A. Total number l.s. parameters = 232. R1 = 0.047for
(18) (a) Kruhlak, N. L.; Wang, M.; Boorman, P. M.; Parvez, M.;
McDonald, R. Inorg. Chem. 2001, 40, 3141–3148. (b) Boorman, P. M.;
Wang, M.; Parvez, M. J. Chem. Soc., Chem. Commun. 1995, 999–1000.
˚
2615 Fo > 4σ(Fo) and 0.052 for all 7163 data. wR2 = 0.139, GOF = 1.036,
restrained GOF = 1.036 for all data.
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SCHEME 8. Synthesis of cis-N-Tosyl Aziridine Tosylate Derivatives 14a,b
1H-1H, 1H-13C COSY, NOE, and HRMS studies. The solid
state structure of 1523 was confirmed by single-crystal X-ray
analysis (Figure 2).
SCHEME 9. Reaction of cis-N-Tosyl Aziridine Tosylate Deri-
vative 14a with 1
ogy was extended to the reaction of cis-aziridino tosylates
14a and 14b with 1. The cis-N-tosyl aziridino-alcohols 13a,b
were synthesized by using the literature procedure reported
by O’Brien et al.19 This procedure starts with cyclohexenol
derivatives 12a,b, prepared by Luche20 reduction of the
cyclohexenones 11a,b. Aziridination of 12a,b with the Sharp-
less aziridination protocol13 [cyclo-hexenol, 3 mmol; CAT,
3.3 mmol; PTAB, 0.3 mmol; 15 mL of CH3CN, rt, 16 h] gave
hydroxy aziridines 13a,b in high yields (80-85%) and with a
satisfactory degree of cis selectivity (Scheme 8).
The cis- and trans-aziridines 13a,b can be separated by
chromatography to give 44-65% isolated yields of cis-13a,b.
Alternatively, an oxidation-reduction sequence (via the
keto aziridines21) can be utilized to produce single diastere-
omers of cis-hydroxy aziridines 13a,b. Reduction of the keto
aziridines with L-selectride in THF at -78 °C furnished
cis-aziridino alcohols 13a,b in good yields with high stereo-
selectivity.22 Further, tosylation of cis-13a,b with p-toluenesul-
fonyl chloride, triethylamine, pyridine, and DMAP in CH2Cl2
at -15 °C for 24 h furnished the corresponding cis-N-tosyl
aziridine tosylates 14a,b in 60-65% yields (Scheme 8).
FIGURE 2. X-ray structures of compounds 15 and 16.
The absence of thia-aza-Payne rearrangement in the case of
14a is certainly an expected result. The formation of aza anion
and tosylate leaving group (intermediate I) are cis to each
other, and as a result it cannot undergo intramolecular SN2
displacement of tosylate by aza anion to give intermediate II
(Scheme 10). Alternatively, displacement of the tosyl group by
sulfur nucleophile would give a six-membered intermediate
III. This intermediate can lead to dithia-bicyclo[3.2.1]octane
derivative 15 by an internal redox process18 with elimination
of MoS2/[Mo3S9]2- as byproducts.
When the same reaction was extended to aziridino-tosy-
late 14b with 1 [2.1 equiv; CH3CN, 28 °C, 12 h] an unusual
thia-bicyclo[3.1.1]heptane derivative 16 was obtained as the
exclusive product in 75% yield (Scheme 11). The regio- and
stereochemical outcome of the reaction was confirmed by
solving the solid state structure of compound 1624 by X-ray
crystallographic analysis (Figure 2).
With the pure compounds in hand, the cis-N-tosyl aziridine
tosylate 14a was treated with 1 [2.1 equiv; CH3CN, 28 °C, 12 h]
to furnish exclusively the dithia-bicyclo[3.2.1]octane derivative
15 in 78% yield without going through the thia-aza-Payne-
type rearrangement pathway (Scheme 9). The structure of
compound 15 was confirmed by 1H, 13C NMR, DEPT,
The formation of 16 can be explained as shown in Scheme 12.
First, the cis-aziridine 14b undergoes ring-opening with 1
(19) Rosser, C. M.; Coote, S. C.; Kirby, J. P.; O’ Brien, P.; Caine, D. Org.
Lett. 2004, 6, 4817–4819.
(20) Luche, J.-L. F. J. Am. Chem. Soc. 1978, 100, 2226–2227.
(21) (a) Fioravanti, S.; Pellacani, L.; Tabanella, S.; Tardella, P. A. Tetra-
hedron 2003, 54, 14105–14112. (b) Barros, M. T.; Maycock, C. D.; Ventura,
M. R. Tetrahedron Lett. 2002, 43, 4329–4331.
(23) The structure was solved by direct methods (SIR92). Refinement was
by full-matrix least-squares procedures on F2 by using SHELXL-97. CCDC
No. 648187. Crystal system: monoclinic; space group: P21/c; cell parameters:
˚
˚
˚
a = 12.005(8) A, b =25.176(3) A, c= 10.735(7) A, a= 90.00°, b = 113.31(4)°,
3
g = 90.00°, V = 2979.6(13) A , Z = 8, Fcalcd = 1.41 g cm-3, F(000) = 1327.9,
˚
m = 0.49 mm-1, l = 0.71073 A. Total number l.s. parameters = 351. R1 =
˚
(22) Dechoux, L.; Doris, E.; Mioskowski, C. Chem. Commun. 1996,
549-550 and references cited therein.
0.057 for 6008 Fo > 4σ(Fo) and 0.073 for all 22253 data. wR2 = 0.136, GOF =
1.085, restrained GOF = 1.085 for all data.
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SCHEME 10. Suggested Mechanism for the Formation of Thia-Bicyclo[3.2.1]octane Derivative 15
IV undergoes in situ reductive cleavage of the disulfide bond26
to give the thiolate intermediate V. Both pathways lead
to the same thiolate intermediate V, which can then give
the thia-bicyclo[3.1.1]heptane derivative 16 as shown in
Scheme 12.
SCHEME 11. Reaction of cis-N-Tosyl Aziridine Tosylate De-
rivative 14b with 1
Conclusion
at the more substituted carbon in an SN2 fashion25 to give
intermediate I, which can further go through two different
pathways: path a1 and a2. Inpatha1, it is possible to visualize the
elimination of MoS3 from intermediate I followed by intramo-
lecular displacement of tosylate by the thiolate intermediate Vto
give the product. In path a2, the intermediate I attacks another
aziridine 14b in a similar manner to give the bisalkylated
intermediate II. The intermediate II is readily poised for S-S
bond formation by internal redox process18 with the elimina-
tion of MoS2/[Mo3S9]2- to give disulfide intermediate IV. In
the presence of excess tetrathiomolybdate 1, the intermediate
In conclusion, we have shown that N-tosyl aziridine-
methanol tosylates undergo a new type of thia-aza-Payne-
type rearrangement with tetrathiomolybdate 1 to give the
corresponding thiirane derivatives as the major products and
five-membered cyclic disulfides as the minor products
with good regio- and stereocontrol. However, cis-N-tosyl
aziridine tosylates 14a,b failed to undergo thia-aza-Payne-
type rearrangement with tetrathiomolybdate 1 but led to
the formation of bicyclo[3.2.1]octane derivative 15 and
thia-bicyclo[3.1.1]heptane derivative 16, respectively, as exclu-
sive product.
SCHEME 12. Suggested Mechanism for the Formation of Thia-Bicyclo[3.1.1]heptane Derivative 16
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Experimental Section
68.4, 45.0, 43.6, 21.7, 21.6, 14.1; HR-MS m/z calcd for
C18H21NO5S2 [Mþ þ Na] 418.0759, found 418.0768.
Compounds 2a,12 10,13 13a, and 13b19 were synthesized
according to literature procedure.
Compound 2d: Rf 0.70 (EtOAc/hexanes, 3: 7); colorless syrup;
yield 0.218 g, 76%; IR (neat) νmax 1597, 1365, 1323, 1160, 966,
814, 693 cm-1; 1H NMR (300 MHz, CDCl3) δ 7.79 (d, J = 8.1
Hz, 2H), 7.68 (d, J = 8.1 Hz, 2H), 7.32 (d, J = 8.1 Hz, 2H), 7.31
(d, J = 8.1 Hz, 2H), 4.26 (dd, J = 11.4, 6.3 Hz, 1H), 4.14 (dd,
J = 11.4, 6.0 Hz, 1H), 2.98-2.93 (m, 1H), 2.73-2.67 (m, 1H),
2.44 (s, 3H), 2.43 (s, 3H), 1.85-1.63 (m, 2H), 1.46-1.23 (m, 2H),
0.89 (t, J = 7.5 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ 145.1,
144.3, 136.7, 132.4, 129.9, 129.5, 127.9, 127.5, 68.0, 47.5, 44.9,
30.9, 21.6, 21.5, 20.6, 13.5; HR-MS m/z calcd for C20H25NO5S2
[Mþ þ Na] 446.1072, found 446.1086.
Synthesis of Compound 2b. To a stirred solution of 2-amino-2-
methyl-1,3-propanediol 7 (1.00 g, 9.52 mmol) in dry pyridine
(20 mL) maintained at ice temperature was added a solution of
p-toluenesulfonyl chloride (5.43 g, 28.56 mmol) in pyridine (10
mL) over a 2 h period. The resulting yellow suspension was
refrigerated overnight, acidified with ice-cold 6 N HC1, and then
extracted with methylene chloride (3 ꢀ 20 mL). The combined
extracts were washed with 5% aqueous NaHCO3, (2 ꢀ 10 mL),
dried over MgSO4, and concentrated in vacuo to give a syrupy
residue. Silica gel chromatography (chloroform-methanol,
95:5) of this residue afforded ditosylate 8 (4.43 g, 82%) as a
colorless syrup. This syrup was dissolved in acetonitrile (30 mL)
and K2CO3 (2.16 g, 15.63 mmol) was added and stirred for 1 h at
room temperature. The solvent was removed under reduced
pressure and the residue was partitioned between water (20 mL)
and methylene chloride (20 mL). The organic phase was sepa-
rated, dried over MgSO4, and concentrated under vacuum to
give a syrupy residue. Silica gel chromatography (ethylacetate-
hexanes, 9:1) of this residue afforded 2b27 as a colorless solid. Rf
0.60 (EtOAc/hexanes, 3:7); yield 2.81 g, 91%; mp 90 °C; IR
(neat) νmax 1596, 1367, 1321, 1161, 972, 832, 670 cm-1; 1H NMR
(300 MHz, CDCl3) δ 7.77 (d, J = 8.1 Hz, 4H), 7.35 (d, J = 8.1
Hz, 2H), 7.28 (d, J = 8.1 Hz, 2H), 4.03 (d, J = 10.5 Hz, 1H), 3.93
(d, J = 10.5 Hz, 1H), 2.61 (s, 1H), 2.46 (s, 3H), 2.44 (s, 3H), 2.37
(s, 1H), 1.67 (s, 3H); 13C NMR (75 MHz, CDCl3) δ 145.2, 144.4,
136.9, 132.5, 129.9, 129.6, 127.9, 127.5, 72.9, 46.6, 39.0, 21.7,
21.6, 15.9; HR-MS m/z calcd for C18H21NO5S2 [M þ Naþ]
418.0759, found 418.0766.
General Procedure for the Synthesis of N-Tosyl Aziridine-
methanol Tosylates. To a solution of appropriate aziridino-
alcohols 1013 (0.68 mmol) in CH2Cl2 (2 mL) cooled to -15 °C
was added pyridine (0.17 mL, 2.1 mmol), DMAP (10 mg, 0.08
mmol), and p-toluenesulfonyl chloride (0.270 g, 1.4 mmol).
After stirring for 24 h at -15 °C, the solution was diluted with
ether at -15 °C (50 mL) and washed with water, 1 M HCl,
saturated NaHCO3, and water. The organic phase was dried
over MgSO4 and concentrated in vacuo and the crude product
was purified by flash column chromatography (230-400 mesh,
eluting with 20% EtOAc/hexanes) to give the corresponding
N-tosyl aziridinemethanol tosylates 2 in good yields.
Compound 2e: Rf 0.70 (EtOAc/hexanes, 3:7); yield 0.213 g,
72%; IR (neat) νmax 1597, 1364, 1324, 1160, 1094, 965, 814, 693,
667 cm-1; 1H NMR (300 MHz, CDCl3) δ 7.79 (d, J = 8.4 Hz,
2H), 7.68 (d, J = 8.4 Hz, 2H), 7.32 (d, J = 8.4 Hz, 2H), 7.31 (d,
J = 8.4 Hz, 2H), 4.27 (dd, J = 10.8, 5.7 Hz, 1H), 4.14 (dd, J =
10.8, 6.3 Hz, 1H), 2.98-2.93 (m, 1H), 2.71-2.66 (m, 1H), 2.45 (s,
3H), 2.44 (s, 3H), 1.77-1.70 (m, 2H), 1.29-1.27 (m, 4H), 0.85 (t,
J = 6.9 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ 145.1, 144.3,
136.7, 132.4, 129.9, 129.5, 127.9, 127.5, 127.4, 68.0, 47.7, 44.9,
29.4, 28.8, 22.0, 21.6, 21.5, 13.8; HR-MS m/z calcd for
C21H27NO5S2 [Mþ þ Na] 460.1228, found 460.1239.
Compound 2f: Rf 0.70 (EtOAc/hexanes, 3:7); yield 0.184 g,
60%; IR (neat) νmax 1597, 1365, 1325, 1160, 1095, 969, 814, 693,
666 cm-1; 1H NMR (300 MHz, CDCl3) δ 7.79 (d, J = 8.4 Hz,
2H), 7.68 (d, J = 8.4 Hz, 2H), 7.32 (d, J = 8.4 Hz, 2H), 7.30 (d,
J = 8.4 Hz, 2H), 4.27 (dd, J = 10.8, 5.7 Hz, 1H), 4.15 (dd, J =
10.8, 6.3 Hz, 1H), 2.96 (dd, J = 10.2, 5.7 Hz, 1H), 2.69 (dd, J =
10.2, 6.6 Hz, 1H), 2.44 (s, 3H), 2.43 (s, 3H), 1.74-1.69 (m, 1H),
1.28-1.24 (m, 7H), 0.85 (t, J = 6.3 Hz, 3H); 13C NMR (75 MHz,
CDCl3) δ 145.1, 144.3, 136.7, 132.4, 129.9, 129.5, 127.8, 127.5,
127.5, 67.9, 47.7, 44.9, 31.0, 29.0, 26.9, 22.3, 21.6, 21.5, 13.8; HR-
MS m/z calcd for C22H29NO5S2 [Mþ þ Na] 474.1385, found
474.1385.
Compound 2g: Rf 0.70 (EtOAc/hexanes, 3:7); yield 0.178 g,
64%; IR (neat) νmax 1596, 1368, 1335, 1160, 962, 834, 678 cm-1
;
1H NMR (300 MHz, CDCl3) δ 7.77 (d, J = 8.1 Hz, 2H), 7.69 (d,
J = 8.1 Hz, 2H), 7.33 (d, J = 8.1 Hz, 2H), 7.32 (d, J = 8.1 Hz,
2H), 4.07 (dd, J = 6.6, 1.0 Hz, 1H), 3.06 (dd, J = 13.5, 6.6 Hz,
1H), 2.83-2.76 (m, 1H), 2.45 (s, 3H), 2.44 (s, 3H), 1.56-1.42 (m,
1H), 1.38-1.23 (m, 1H), 0.86 (t, J = 7.2 Hz, 3H); 13C NMR (75
MHz, CDCl3) δ 145.2, 144.8, 134.3, 132.3, 129.9, 129.6, 128.0,
127.9, 66.1, 45.2, 40.9, 21.6, 20.2, 11.5; HR-MS m/z calcd for
C19H23NO5S2Naþ [M þ Naþ] 432.0915, found 432.0922.
Compound 2h: Rf 0.70 (EtOAc/hexanes, 3:7); colorless syrup;
yield 0.186 g, 65%; IR (neat) νmax 1597, 1366, 1328, 1161, 1092,
975, 815, 720, 667 cm-1; 1H NMR (300 MHz, CDCl3) δ 7.77 (d,
J = 8.1 Hz, 2H), 7.69 (d, J = 8.1 Hz, 2H), 7.33 (d, J = 8.1 Hz,
4H), 3.99 (d, J = 6.6 Hz, 2H), 3.04 (dd, J = 13.8, 6.6 Hz, 1H),
2.86 (dd, J = 13.8, 7.5 Hz, 1H), 2.45 (s, 6H), 1.44-1.17 (m, 4H),
0.84 (t, J = 6.6 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ 145.2,
144.8, 134.3, 132.2, 129.9, 129.6, 127.9, 127.8, 66.1, 43.6, 40.8,
28.6, 21.6, 20.4, 13.5; HR-MS m/z calcd for C20H25NO5S2 [Mþ
þ Na] 446.1072, found 446.1081.
Compound 2c: Rf 0.65 (EtOAc/hexanes, 3:7); colorless syrup;
yield 0.210 g, 78%; IR (neat) νmax 1597, 1495, 1453, 1361, 1324,
1177, 1092, 970, 815, 709, 685, 664 cm-1; 1H NMR (300 MHz,
CDCl3) δ 7.79 (d, J = 8.4 Hz, 2H), 7.64 (d, J = 8.4 Hz, 2H), 7.30
(d, J = 8.4 Hz, 4H), 4.17 (dd, J = 11.0, 5.7 Hz, 1H), 3.96 (dd,
J = 11.0, 6.3 Hz, 1H), 2.98-3.03 (m, 1H), 2.73-2.79 (m, 1H),
2.44 (s, 6H), 1.56 (d, J = 6.3 Hz, 3H); 13C NMR (75 MHz,
CDCl3) δ 145.1, 144.3, 137.0, 132.4, 129.8, 129.5, 127.8, 127.4,
(24) The structure was solved by direct methods (SIR92). Refinement was
by full-matrix least-squares procedures on F2 by using SHELXL-97. CCDC
No. 648188. Crystal system: triclinic, space group: P1; cell parameters: a =
˚
˚
˚
7.530(2) A, b = 8.964(2) A, c = 11.913(3) A, a = 77.985(4)°, b = 75.57(4)°, g =
Compound 2i: Rf 0. 70 (EtOAc/hexanes, 3:7); colorless syrup;
yield 0.188 g, 70%; IR (neat) νmax 1592, 1371, 1331, 1168, 966,
835, 671 cm-1; 1H NMR (300 MHz, CDCl3) δ 7.76 (d, J = 8.1
Hz, 2H), 7.68 (d, J = 8.1 Hz, 2H), 7.33 (d, J = 8.1 Hz, 4H), 3.99
(d, J = 6.3 Hz, 2H), 3.03-2.92 (m, 2H), 2.45 (s, 6H), 1.17 (d, J =
5.4 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ 145.2, 144.8, 134.5,
132.3, 129.9, 129.7, 127.8, 65.9, 40.7, 38.9, 21.6, 11.9; HR-MS
m/z calcd for C18H21NO5S2 [Mþ þ Na] 418.0759, found 418.0759.
Compound 2j: Rf 0.60 (EtOAc/hexanes, 3:7); yield 0.183 g,
3
88.780(4)°,V= 761.3(1) A ,Z=2,Fcalcd =1.30gcm-3,F(000) = 316, m=0.35
˚
mm-1, l= 0.71073 A. Total number l.s. parameters = 178. R1 = 0.084 for 258 Fo
˚
> 4σ(Fo) and 0.103 for all 6646 data. wR2 = 0.225, GOF = 1.030, restrained
GOF = 1.030 for all data.
ꢀ
(25) (a) Forbeck, E. M.; Evans, C. D.; Gilleran, J. A.; Li, P.; Joullie,
M. M. J. Am. Chem. Soc. 2007, 129, 14463–14469. (b) Li, P.; Forbeck, E. M.;
ꢀ
Evans, C. D.; Joullie, M. M. Org. Lett. 2006, 8, 5105–5107. (c) Lin, P.; Bellos,
K.; Stamm, H.; Onistschenko, A. Tetrahedron 1992, 48, 2359–2372.
(26) (a) Pan, W. H.; Harmer, M. A.; Halbert, T. R.; Stiefel, E. I. J. Am.
Chem. Soc. 1984, 106, 459–460. (b) Coyle, C. L.; Harmer, M. A.; George,
G. N.; Daage, M.; Stiefel, E. I. Inorg. Chem. 1990, 29, 14-19 and references
cited therein. (c) Prabhu, K. R.; Sivanand, P.; Chandrasekaran, S. Angew.
Chem., Int. Ed. 2000, 39, 4316–4319.
66%; IR (neat) νmax 1595, 1366, 1326, 965, 816, 682, 665 cm-1
;
1H NMR (300 MHz, CDCl3) δ 7.77 (d, J = 8.1 Hz, 2H), 7.64 (d,
J = 8.1 Hz, 2H), 7.31 (d, J = 8.1 Hz, 2H), 7.29 (d, J = 8.1 Hz,
(27) Chao, B.; Dittmer, D. C. Tetrahedron Lett. 2001, 42, 5789–5791.
J. Org. Chem. Vol. 75, No. 16, 2010 5539

Sureshkumar et al.
JOCArticle
2H), 4.02 (dd, J = 10.8, 5.7 Hz, 1H), 3.86 (dd, J = 10.8, 6.6 Hz,
1H), 3.13 (t, J = 6.6 Hz, 1H), 2.45 (s, 3H), 2.43 (s, 3H), 1.22 (s, 3H);
13C NMR (75 MHz, CDCl3) δ 145.1, 144.0, 137.5, 132.3, 129.9,
129.5, 127.8, 127.3, 67.3, 51.2, 48.1, 21.6, 21.5, 21.2, 20.8; HR-MS
m/z calcd for C19H23NO5S2 [Mþ þ Na] 432.0915, found 432.0927.
General Procedure for the Synthesis of cis-N-Tosyl Aziridine-
methanol Tosylates 14. To a solution of appropriate cis-aziridi-
no-alcohols 1319 (0.68 mmol) in CH2Cl2 (2 mL) cooled to -15 °C
was added pyridine (0.17 mL, 2.1 mmol), DMAP (10 mg, 0.08
mmol), and p-toluenesulfonyl chloride (0.270 g, 1.4 mmol). After
being stirred for 24 h at -15 °C, the solutionwas dilutedwith ether
at -15 °C (50 mL) and washed with water, 1 M HCl, saturated
NaHCO3, and water. The organic phase was dried over MgSO4
and concentrated in vacuo. Purification by flash column chroma-
tography on silica gel (20% EtOAc/hexanes) gave the correspond-
ing cis-aziridino-tosylates 14 as a colorless syrup in good yields.
Compound 14a: Rf 0.40 (EtOAc/hexanes, 3:7); yield 0.186 g,
65%; IR (neat) νmax 1597, 1365, 1327, 1189, 1176, 1161, 1093,
989, 814, 726, 670 cm-1; 1H NMR (300 MHz, CDCl3) δ 7.82 (d,
J = 8.1 Hz, 2H), 7.64 (d, J = 8.1 Hz, 2H), 7.32 (d, J = 8.1 Hz,
2H), 7.31 (d, J = 8.1 Hz, 2H), 4.70-4.64 (m, 1H), 3.19 (t, J = 6.6
Hz, 1H), 3.01 (dd, J = 7.2, 3.3 Hz, 1H), 2.44 (s, 6H), 1.91-1.66
(m, 2H), 1.59-1.53 (s, 3H), 1.31-1.10 (m, 1H); 13C NMR (75
MHz, CDCl3) δ 144.7, 144.5, 134.5, 133.6, 129.7, 129.5, 127.9,
127.6, 75.8, 41.6, 40.7, 25.4, 21.6, 21.5, 20.8, 19.9; HR-MS m/z
calcd for C20H23NO5S2 [Mþ þ Na] 444.0915, found 444.0920.
Compound 14b: Rf 0.50 (EtOAc/hexanes, 3:7); yield 0.177 g,
60%; IR (neat) νmax 1597, 1321, 1188, 1175, 1157, 1090, 940,
873, 814, 736, 666 cm-1; 1H NMR (300 MHz, CDCl3) δ 8.08 (d,
J = 8.1 Hz, 2H), 7.81 (d, J = 8.1 Hz, 2H), 7.29 (d, J = 8.1 Hz,
2H), 7.24 (d, J = 8.1 Hz, 2H), 4.76-4.70 (m, 1H), 3.23 (d, J = 3.9
Hz, 1H), 2.44 (s, 6H), 2.40 (s, 3H), 2.00-1.83 (m, 1H), 1.67 (s, 3H),
1.62-1.28 (m, 4H), 1.27-1.16 (m, 1H); 13C NMR (75 MHz,
CDCl3) δ 144.6, 143.6, 137.6, 133.8, 129.7, 129.2, 127.5, 127.4,
76.1, 53.1, 48.7, 29.9, 25.4, 21.6, 21.5, 20.6, 18.9; HR-MS m/z calcd
for C21H25NO5S2 [Mþ þ Na] 458.1072, found 458.1083.
NMR (300 MHz, CDCl3) δ 7.74 (d, J = 8.1 Hz, 2H), 7.32 (d,
J = 8.1 Hz, 2H), 4.77 (t, J = 6.0 Hz, 1H), 3.35-3.26 (m, 1H),
3.13-3.05 (m, 1H), 2.79 (dd, J = 10.8, 5.1 Hz, 1H), 2.71-2.65
(m, 1H), 2.43 (s, 3H), 1.77-1.68 (m, 1H), 1.54-1.32 (m, 3H),
0.92 (t, J = 7.2 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ 143.7,
136.8, 129.8, 127.0, 46.9, 41.7, 40.9, 37.4, 22.2, 21.5, 13.6; HR-
MS m/z calcd for C13H19NO2S2 [Mþ þ Na] 308.0755, found
308.0752.
Compound 3e: Rf 0.60 (EtOAc/toluene, 5:95); yield 0.091 g,
61%; IR (neat) νmax 3276, 1326, 1159, 1093, 813, 663 cm-1; 1H
NMR (300 MHz, CDCl3) δ 7.74 (d, J = 8.1 Hz, 2H), 7.31 (d, J =
8.1 Hz, 2H), 4.84 (t, J = 6.0 Hz, 1H), 3.33-3.25 (m, 1H),
3.14-3.05 (m, 1H), 2.79 (dd, J = 11.1, 5.1 Hz, 1H), 2.67 (dd,
J = 11.1, 5.4 Hz, 1H), 2.43 (s, 3H), 1.79-1.72 (m, 1H), 1.38-1.33
(m, 5H), 0.89 (t, J = 6.9 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ
143.6, 136.8, 129.8, 127.0, 46.9, 41.9, 40.9, 35.1, 31.1, 22.2, 21.5,
13.9; HR-MS m/z calcd for C14H21NO2S2 [Mþ þ Na] 322.0911,
found 322.0921.
Compound 3f: Rf 0.60 (EtOAc/toluene, 5:95); yield 0.091 g,
58%; IR (neat) νmax 3275, 1326, 1159, 1094, 813, 664 cm-1; 1H
NMR (300 MHz, CDCl3) δ 7.74 (d, J = 8.1 Hz, 2H), 7.31 (d,
J = 8.1 Hz, 2H), 4.75 (t, J = 6.0 Hz, 1H), 3.35-3.27 (m, 1H),
3.13-3.04 (m, 1H), 2.79 (dd, J = 10.5, 5.4 Hz, 1H), 2.68 (dd, J =
10.5, 6.6 Hz, 1H), 2.43 (s, 3H), 1.79-1.70 (m, 1H), 1.40-1.28 (m,
7H), 0.86 (t, J = 6.3 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ
143.6, 136.7, 128.9, 127.0, 46.9, 41.9, 40.9, 35.3, 31.2, 28.7, 22.5,
21.5, 13.9; HR-MS m/z calcd for C15H23NO2S2 [Mþ þ Na]
336.1068, found 336.1068.
Compound 3g: Rf 0.60 (EtOAc/toluene, 5:95); yield 0.070 g,
52%; IR (neat) νmax 3278, 1324, 1159, 1094, 814, 664 cm-1; 1H
NMR (300 MHz, CDCl3) δ 7.76 (d, J = 8.1 Hz, 2H), 7.32 (d,
J = 8.1 Hz, 2H), 4.21 (t, J = 5.4 Hz, 1H), 3.44-3.32 (m, 1H),
3.18-2.89 (m, 3H), 2.44 (s, 3H), 1.99-1.89 (m, 2H), 0.91 (t, J =
7.5 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ 143.4, 136.9, 136.3,
129.7, 127.2, 123.1, 39.9, 21.5, 20.6, 13.9; HR-MS m/z calcd for
C12H17NO2S3 [Mþ þ Na] 294.0598, found 294.0602.
Compound 3h: Rf 0.60 (EtOAc/toluene, 5:95); yield 0.074 g,
52%; IR (neat) νmax 3280, 1327, 1159, 1094, 814, 665 cm-1; 1H
NMR (300 MHz, CDCl3) δ 7.77 (d, J = 8.1 Hz, 2H), 7.32 (d,
J = 8.1 Hz, 2H), 4.92 (t, J = 5.1 Hz, 1H), 3.41-3.33 (m, 1H),
3.16-2.91 (m, 3H), 2.43 (s, 3H), 1.82-1.73 (m, 1H), 1.57-1.26 (m,
3H), 0.94 (t, J = 7.2 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ 143.7,
136.8, 129.8, 127.0, 44.4, 41.3, 38.6, 32.4, 22.8, 21.5, 13.6; HR-MS
m/z calcd for C13H19NO2S2 [Mþ þ Na] 308.0755, found 308.0763.
Compound 3j: Rf 0.60 (EtOAc/toluene, 5:95); yield 0.087 g,
General Procedure for the Reaction of N-Tosyl Aziridine-
methanol Tosylates with Benzyltriethylammonium Tetrathiomo-
lybdate 1. To a well-stirred solution of the appropriate N-tosyl
aziridino-tosylate 2 (0.50 mmol) in CH3CN (8 mL) was added
tetrathiomolybdate 1 (0.639 g, 1.05 mmol) at once with stirring
at room temperature (28 °C) until the disappearance of starting
material (TLC, 5-13 h). The solvent was evaporated under
reduced pressure and the black residue was extracted with
CH2Cl2:Et2O (1:5, 3 ꢀ 10 mL) and filtered through a Celite
pad. The filtrate was concentrated and the residue was purified
by flash column chromatography on silica gel (230-400 mesh,
eluting with 2% EtOAc/toluene) to give the appropriate thiirane
derivatives 3 and cyclic disulfides 4 in good yields.
Compound 3b: Rf 0.60 (EtOAc/toluene, 5:95); colorless liquid;
yield 0.080 g, 62%; IR (neat) νmax 3279, 1329, 1159, 1093, 813,
665 cm-1; 1H NMR (300 MHz, CDCl3) δ 7.73 (d, J = 8.1 Hz,
2H), 7.32 (d, J = 8.1 Hz, 2H), 4.73 (t, J = 6.3 Hz, 1H), 3.27 (dd,
J = 12.6, 5.4 Hz, 1H), 3.15 (dd, J = 12.6, 7.2 Hz, 1H), 2.49 (s, 1H),
2.43(s,3H), 2.33 (s, 1H), 1.61 (s, 3H); 13C NMR (75 MHz, CDCl3)
δ 143.6, 136.8, 129.8, 126.9, 50.4, 44.1, 31.3, 24.2, 21.5; HR-MS m/
z calcd for C11H15NO2S2 [Mþ þ Na] 280.0442, found 280.0451.
Compound 3c: Rf 0.30 (EtOAc/hexanes, 3:7); yield 0.085 g,
65%; mp 92 °C; IR (neat) νmax 3280, 1597, 1441, 1324, 1159,
1093, 1050, 813, 664 cm-1; 1H NMR (400 MHz, CDCl3) δ 7.74,
(d, J = 8.4 Hz, 2H), 7.31 (d, J = 8.4 Hz, 2H), 4.91 (t, J = 6.4 Hz,
1H), 3.29-3.22 (m, 1H), 3.14-3.301 (m, 1H), 2.76-2.72 (m,
2H), 2.42 (s, 3H), 1.44 (d, J = 5.6 Hz, 3H); 13C NMR (75 MHz,
CDCl3) δ 143.6, 136.7, 129.8, 127.0, 46.8, 42.0, 36.4, 21.4, 20.9;
HR-MS m/z calcd for C11H15 NO2S2 [M þ Naþ] 280.0442,
found 280.0475.
64%; IR (neat) νmax 3280, 1597, 1325, 1159, 1092, 814, 664 cm-1
;
1H NMR (300 MHz, CDCl3) δ 7.77 (d, J = 8.1 Hz, 2H), 7.33 (d,
J = 8.1 Hz, 2H), 4.75 (t, J = 5.4 Hz, 1H), 3.39-3.30 (m, 1H),
3.21-3.13 (m, 1H), 2.91 (t, J = 6.6 Hz, 1H), 2.45 (s, 3H), 1.54 (s,
3H), 1.52 (s, 3H); 13C NMR (75 MHz, CDCl3) δ 143.7, 136.8,
129.8, 127.4, 67.3, 47.0, 45.1, 30.2, 22.9, 21.7; HR-MS m/z calcd
for C12H17NO2S2 [Mþ þ Na] 294.0598, found 294.0604.
Compound 4a: Rf 0.70 (EtOAc/toluene, 5:95); yellow solid;
mp 123 °C; yield 0.110 g, 80%; IR (neat) νmax 3265, 1334, 1158,
1092, 814, 664 cm-1; 1H NMR (300 MHz, CDCl3) δ 7.78 (d, J =
8.1 Hz, 2H), 7.33 (d, J = 8.1 Hz, 2H), 5.23 (d, J = 9.9 Hz, 1H),
4.62-4.56 (m, 1H), 3.09 (dd, J = 11.7, 5.1 Hz, 2H), 2.95 (dd, J =
11.7, 2.4 Hz, 2H), 2.44 (s, 3H); 13C NMR (75 MHz, CDCl3) δ
143.9, 137.6, 129.9, 126.9, 58.7, 44.6, 21.5; HR-MS m/z calcd for
C10H13NO2S3 [Mþ þ Na] 298.0035, found 298.0015.
Compound 4b: Rf 0.70 (EtOAc/toluene, 5:95); yellow solid;
mp 102 °C; yield 0.023 g, 16%; IR (neat) νmax 3274, 1336, 1162,
1088, 816, 668 cm-1; 1H NMR (300 MHz, CDCl3) δ 7.81 (d, J =
8.1 Hz, 2H), 7.31 (d, J = 8.1 Hz, 2H), 5.36 (s, 1H), 3.21 (d, J =
11.7 Hz, 2H), 2.93 (d, J = 11.7 Hz, 2H), 2.44 (s, 3H), 1.58 (s, 3H);
13C NMR (75 MHz, CDCl3) δ 143.6, 139.3, 129.7, 127.1, 68.4,
49.8, 22.6, 21.5; HR-MS m/z calcd for C11H15NO2S3 [Mþ þ Na]
312.0163, found 312.0174.
Compound 3d: Rf 0.60 (EtOAc/toluene, 5:95); yield 0.088 g,
62%; IR (neat) νmax 3279, 1326, 1159, 1093, 813, 666 cm-1; 1H
5540 J. Org. Chem. Vol. 75, No. 16, 2010

Sureshkumar et al.
JOCArticle
Compound 4i: Rf 0.70 (EtOAc/toluene, 5:95); yield 0.087 g,
Compound 4c: Rf 0.40 (EtOAc/hexanes, 3:7); yield 0.023 g,
16%; mp 93 °C; IR (neat) νmax 3274, 2923, 2853, 1743, 1333,
1159, 1091, 813, 666 cm-1; 1H NMR (400 MHz, CDCl3) δ 7.77
(d, J = 8.4 Hz, 2H), 7.33 (d, J = 8.4 Hz, 2H), 5.05, (d, J = 10.4
Hz, 1H), 4.16-4.12 (m, 1H), 3.42-3.33 (m, 1H), 3.13 (dd, J =
11.6, 4.8 Hz, 1H), 2.89 (dd, J = 11.6, 2.0 Hz, 1H), 2.45 (s, 3H),
1.24 (d, J = 6.8 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ 143.9,
137.8, 129.9, 126.9, 64.7, 55.4, 42.2, 21.5, 20.1; HR-MS m/z calcd
for C11H15NO2S3 [M þ Naþ] 312.0163, found 312.0169.
Compound 4d: Rf 0.70 (EtOAc/toluene, 5:95); yield 0.025 g,
16%; IR (neat) νmax 3271, 1335, 1159, 1092, 814, 666 cm-1; 1H
NMR (300 MHz, CDCl3) δ 7.79 (d, J = 8.1 Hz, 2H), 7.35 (d, J =
8.1 Hz, 2H), 5.15 (d, J = 10.0 Hz, 1H), 4.23-4.19 (m, 1H),
3.27-3.23 (m, 1H), 3.09 (dd, J = 11.6, 4.8 Hz, 1H), 2.93 (dd, J =
11.6, 2.0 Hz, 1H), 2.46 (s, 3H), 1.49-1.22 (m, 4H), 0.96 (t, J = 7.2
Hz, 3H); 13C NMR (75 MHz, CDCl3) δ 143.9, 137.9, 129.9, 126.9,
63.6, 61.3, 42.9, 36.1, 21.5, 21.0, 13.5; HR-MS m/z calcd for
C13H19NO2S3 [Mþ þ Na] 340.0476, found 340.0478.
60%; IR (neat) νmax 3281, 1336, 1158, 1091, 1048, 814, 665 cm-1
;
1H NMR (300 MHz, CDCl3) δ 7.78 (d, J = 8.1 Hz, 2H), 7.32 (d,
J = 8.1 Hz, 2H), 5.05 (d, J = 10.2 Hz, 1H), 4.35-4.28 (m, 1H),
3.64-3.56 (m, 1H), 3.15 (dd, J = 11.4, 4.5 Hz, 1H), 2.81 (dd, J =
11.4, 1.8 Hz, 1H), 2.44 (s, 3H), 1.33 (d, J = 7.2 Hz, 3H); 13C
NMR (75 MHz, CDCl3) δ 154.6, 143.8, 129.9, 126.9, 61.9, 53.9,
43.2, 21.6, 13.8; HR-MS m/z calcd for C11H15NO2S3 [Mþ þ Na]
312.0163, found 312.0173.
Compound 4j: Rf 0.70 (EtOAc/toluene, 5:95); yield 0.024 g,
16%; mp 108 °C; IR (neat) νmax 3276, 1327, 1159, 1092, 813, 671
cm-1; 1H NMR (300 MHz, CDCl3) δ 7.77 (d, J = 8.1 Hz, 2H),
7.33 (d, J = 8.1 Hz, 2H), 4.97 (d, J = 10.2 Hz, 1H), 3.90-3.84 (m,
1H), 3.19 (dd, J = 10.8, 4.8 Hz, 1H), 2.78 (dd, J = 10.8, 2.7 Hz,
1H), 2.44 (s, 3H), 1.41 (s, 6H); 13C NMR (75 MHz, CDCl3) δ
143.8, 137.9, 129.9, 126.9, 66.7, 61.9, 41.0, 27.5, 22.2, 21.5; HR-MS
m/z calcd for C12H27NO2S3 [Mþ þ Na] 326.0319, found 326.0328.
Compound 15: Rf 0.60 (EtOAc/toluene, 5:95); yellow solid;
mp 152 °C; yield 0.123 g, 78%; IR (neat) νmax 3264, 1333, 1168,
1061, 1031, 888, 821, 684 cm-1; 1H NMR (300 MHz, CDCl3) δ 7.79
(d, J = 8.1 Hz, 2H), 7.35 (d, J = 8.1 Hz, 2H), 5.41 (d, J = 7.6 Hz,
1H), 4.00-3.97 (m, 1H), 3.56 (d, J = 2.0 Hz, 2H), 2.43 (s, 3H),
2.33-2.22 (m, 2H), 2.05-1.93 (m, 4H); 13C NMR (75 MHz, CDCl3)
δ 144.2, 139.3, 130.1, 127.1, 62.2, 47.5, 27.2, 21.6, 16.5; HR-MS m/z
calcd for C13H17NO2S3 [Mþ þ Na] 338.0319, found 338.0329.
Compound 16: Rf 0.60 (EtOAc/toluene, 5:95); colorless solid;
mp 148 °C; yield 0.111 g, 75%; IR (neat) νmax 3270, 1332, 1161,
1071, 1038, 897, 810, 669 cm-1; 1H NMR (300 MHz, CDCl3) δ
7.79 (d, J = 8.1 Hz, 2H), 7.31 (d, J = 8.1 Hz, 2H), 5.22 (d, J =
9.8 Hz, 1H), 4.22 (dd, J = 9.9, 5.9 Hz, 1H), 3.29 (t, J = 5.0 Hz,
1H), 2.43 (s, 3H), 2.21-2.14 (m, 1H), 1.88-1.76 (m, 2H),
1.69-1.61 (m, 3H), 1.14 (s, 3H); 13C NMR (75 MHz, CDCl3)
δ 143.8, 138.0, 129.8, 126.9, 61.8, 58.5, 47.9, 29.2, 26.2, 21.5,
20.6, 16.3; HR-MS m/z calcd for C14H19NO2S2 [Mþ þ Na]
320.0755, found 320.0766.
Compound 4f: Rf 0.70 (EtOAc/toluene, 5:95); yield 0.024 g,
14%; IR (neat) νmax 3271, 1336, 1159, 1092, 814, 665 cm-1; 1H
NMR (300 MHz, CDCl3) δ 7.77 (d, J = 8.1 Hz, 2H), 7.33 (d, J =
8.1 Hz, 2H), 5.08 (d, J = 9.9 Hz, 1H), 4.22-4.16 (m, 1H),
3.23-3.17 (m, 1H), 3.08 (dd, J = 11.4, 4.5 Hz, 1H), 2.92 (dd,
J = 11.4, 1.8 Hz, 1H), 2.44 (s, 3H), 1.47-1.16 (m, 8H), 0.86 (t, J =
6.6 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ 143.9, 137.9, 129.9,
126.9, 63.5, 61.6, 42.9, 34.0, 31.2, 27.5, 22.4, 21.5, 13.9; HR-MS
m/z calcd for C15H23NO2S3 [Mþ þ Na] 368.0789, found 368.0800.
Compound 4g: Rf 0.70 (EtOAc/toluene, 5:95); yield 0.020 g,
13%; IR (neat) νmax 3274, 1336, 1158, 1092, 814, 667 cm-1; 1H
NMR (300 MHz, CDCl3) δ 7.78 (d, J = 8.1 Hz, 2H), 7.32 (d,
J = 8.1 Hz, 2H), 5.07 (d, J = 10.2 Hz, 1H), 4.43-4.37 (m, 1H),
3.45-3.39 (m, 1H), 3.11 (dd, J = 11.4, 3.9 Hz, 1H), 2.78 (dd, J =
11.4, 2.1 Hz, 1H), 2.44 (s, 3H), 1.88-1.62 (m, 2H), 0.97 (t, J =
7.2 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ 143.8, 138.1, 129.9,
126.9, 61.9, 59.9, 43.2, 22.2, 21.5, 13.6; HR-MS m/z calcd for
C12H17NO2S3 [Mþ þ Na] 326.0319, found 326.0334.
Compund 4h: Rf 0.70 (EtOAc/toluene, 5:95); yield 0.021 g, 13%;
IR (neat) νmax 3271, 1335, 1157, 1092, 814, 664 cm-1; 1H NMR
(300 MHz, CDCl3) δ 7.78 (d, J = 8.1 Hz, 2H), 7.33 (d, J = 8.1 Hz,
2H), 5.10 (d, J = 10.2 Hz, 1H), 4.41-4.34 (m, 1H), 3.51-3.45 (m,
1H), 3.12 (dd, J = 11.1, 4.2 Hz, 1H), 2.81 (dd, J = 11.1, 1.8 Hz,
1H), 2.44 (s, 3H), 1.77-1.52 (m, 2H), 1.38-1.26 (m, 2H), 0.86 (t,
J = 7.2 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ 143.8,
138.1, 129.9, 126.9, 60.2, 59.9, 43.1, 30.9, 22.5, 21.5, 13.9; HR-
MS m/z calcd for C13H19NO2S3 [Mþ þ Na] 340.0476, found
340.0483.
Acknowledgment. We thank CSIR, New Delhi for a Senior
Research Fellowship to D.S. and a Shyam Prasad Mukherji
fellowship to V.G. DST, New Delhi is thanked for the CCD
X-ray facility and the JC Bose National Fellowship to SCN.
Supporting Information Available: 1H, 13C spectra for all
new compounds and X-ray crystallographic data for com-
pounds 3c, 4c, 4j, 15, and 16. This material is available free of
charge via the Internet at http://pubs.acs.org.
J. Org. Chem. Vol. 75, No. 16, 2010 5541