634
N. Jain, M. A. Ciufolini
Letter
Synlett
(8) As found, for example, in a Fukuyama sulfonamide, see: Kan, T.;
Fukuyama, T. Chem. Commun. 2004, 353.
70.9, 48.9, 39.5, 23.0, 21.6. HRMS: m/z [M + Na]+ calcd for
C
20H19NO3SNa: 376.0983; found: 376.0983.
(9) However, oxidative cyclization of naphtholic carboxylic acids
and alcohols to spirocyclic lactones and ethers, respectively, is
documented. For examples involving oxidation with hyperva-
lent iodine reagents, see: (a) Dean, F. M.; Herbin, G. A.; Matkin,
D. A.; Price, A. W.; Robinson, M. L. J. Chem. Soc., Perkin Trans. 1
1980, 1986. (b) Dohi, T.; Maruyama, A.; Takenage, N.; Senami,
K.; Minamitsuji, Y.; Fujioka, H.; Caemmerer, S.; Kita, Y. Angew.
Chem. Int. Ed. 2008, 47, 3787. (c) Uyanik, M.; Yasui, T.; Ishihara,
K. Angew. Chem. Int. Ed. 2010, 49, 2175. (d) Dohi, T.; Takenaga,
N.; Nakae, T.; Toyoda, Y.; Yamasaki, M.; Shiro, M.; Fujioka, H.;
Maruyama, A.; Kita, Y. J. Am. Chem. Soc. 2013, 135, 4558. For
examples involving oxidation with other reagents, see: (e) DDQ:
De Koning, C. B.; Giles, R. G. F.; Engelhardt, L. M.; White, A. H. J.
Chem. Soc., Perkin Trans. 1 1988, 3209. (f) KOBr: Katsuri, T. R.;
Sattigeri, J. A.; Pragnacharyulu, P. V. P.; Cameroon, T. S.; Pradeep,
B. Tetrahedron 1995, 51, 3051. (g) Br3–: Georghiou, P. E.; Ashram,
M.; Clase, H. J.; Bridson, J. N. J. Org. Chem. 1998, 63, 1819.
(h) Pb(OAc)4: Cox, C.; Danishefsky, S. J. Org. Lett. 2000, 2, 3493.
(10) The choice of sulfonamide substrates was motivated by the fact
that they tend to undergo oxidative spirocyclization in excellent
yield (ref. 7).
(11) These materials were prepared from the corresponding naph-
thols by O-allylation, Claisen rearrangement, and further elabo-
ration of the resultant ortho-allylnaphthols in a conventional
fashion, as detailed in the Supporting Information.
(12) (a) Kenner, G. W.; McDermott, J. R.; Sheppard, R. C. Chem.
Commun. 1971, 636. (b) For a review, see: Heidler, P.; Link, A.
Bioorg. Med. Chem. 2005, 13, 585.
(13) Fluoroalcohols such as HFIP are valuable solvents in a number
of reactions involving hypervalent iodine species, see: (a) Dohi,
T.; Yamaoka, N.; Kita, Y. Tetrahedron 2010, 66, 5775. (b) Ito, M.;
Ogawa, C.; Yamaoka, N.; Fujioka, H.; Dohi, T.; Kita, Y. Molecules
2010, 15, 1918.
(14) 1′-Tosyl-1H-spiro[naphthalene-2,2′-pyrrolidin]-1-one (9a);
Typical Procedure: The preparation of this compound illus-
trates the general procedure for the cyclization of substrates 8.
A solution of sulfonamide 8a (20 mg, 0.4 mmol, 1.0 equiv) in
TFA (0.7 mL) was slowly added at room temperature over a
period of 2 min to a solution of DIB (0.44 mmol, 1.1 equiv) in
TFA (0.5 mL) so that the final concentration was 0.3 M. Upon
completion of the reaction (TLC, 10 min), the mixture was evap-
orated to dryness. Chromatographic purification of the residue
(silica gel; EtOAc–hexanes, 1:3) provided 9a (15 mg, 74%) as a
yellow solid; mp 115–117 °C. IR: 1686 cm–1. 1H NMR (300 MHz,
CDCl3): δ = 8.03 (d, J = 7.2 Hz, 1 H), 7.72 (d, J = 8.3 Hz, 2 H), 7.58
(td, J = 7.5, 1.4 Hz, 1 H), 7.36 (td, J = 7.6, 1.1 Hz, 1 H), 7.29–7.24
(m, 3 H), 6.59 (d, J = 9.9 Hz, 1 H), 6.27 (d, J = 9.8 Hz, 1 H), 3.64–
3.60 (m, 2 H), 2.42 (s, 3 H), 2.26–2.03 (m, 2 H), 2.02–1.95 (m,
2 H). 13C NMR (75.5 MHz, CDCl3): δ = 198.4, 143.2, 137.4, 137.1,
136.6, 134.8, 129.3, 128.7, 128.0, 127.7, 127.6, 127.5, 124.5,
1′-(Methylsulfonyl)-2H-spiro[naphthalene-1,2′-pyrrolidin]-
2-one (11a): The cyclization of 2-naphthol-derived substrates
10 was achieved by the same procedure detailed above. Thus,
10a (25 mg) afforded 11a (16 mg, 67%) after column chromatog-
raphy (EtOAc–hexane, 2:3) as a white solid; mp 116–118 °C. IR:
1672 cm–1 1H NMR (300 MHz, CDCl3): δ = 7.62 (d, J = 7.8 Hz,
.
1 H), 7.47–7.42 (m, 2 H), 7.32–7.31 (m, 2 H), 6.17 (d, J = 9.9 Hz,
1 H), 3.96 (dt, J = 8.7, 6.2 Hz, 1 H), 3.76 (dt, J = 8.7, 7.0 Hz, 1 H),
3.10 (s, 3 H), 2.38 (dt, J = 12.0, 7.1 Hz, 1 H), 2.17 (quintet,
J = 6.6 Hz, 2 H), 2.07–1.98 (m, 1 H). 13C NMR (75.5 MHz, CDCl3):
δ = 200.5, 146.5, 146.0, 130.6, 129.8, 128.5, 127.7, 125.8, 123.7,
75.8, 49.9, 44.2, 40.0, 22.8. HRMS: m/z [M + Na]+ calcd for
C
14H15NO3SNa: 300.0670; found: 300.0665.
1′-(Methylsulfonyl)-1H-spiro[naphthalene-2,2′-pyrrolidine]-
1,5′-dione (15a): A solution of 14a (19 mg, 0.1 mmol, 1.0 equiv)
in HFIP (2.0 mL) was added to a solution containing DIB (0.11
mmol, 1.1 equiv) in TFA (0.23 mL) at room temperature so that
the final concentration was 0.05 M. Upon completion of the
reaction (TLC, 5–12 min), the reaction mixture was evaporated
to dryness. Chromatography of the residue (silica gel; EtOAc–
hexane, 3:7) gave 15a (8 mg, 42%) as a white solid; mp 169–
171 °C. IR: 1737, 1686 cm–1. 1H NMR (300 MHz, CDCl3): δ = 8.05
(d, J = 7.7 Hz, 1 H), 7.64 (t, J = 7.5 Hz, 1 H), 7.42 (t, J = 7.6 Hz,
1 H), 7.30–7.27 (m, 1 H), 6.61 (d, J = 9.8 Hz, 1 H), 6.43 (d, J =
9.8 Hz, 1 H), 3.38 (s, 3 H), 2.84–2.58 (m, 2 H), 2.33 (ddd, J = 13.4,
9.4, 3.9 Hz, 1 H), 2.20–2.09 (m, 1 H). 13C NMR (75.5 MHz,
CDCl3): δ = 197.1, 174.7, 137.5, 135.8, 135.3, 128.6, 128.1, 127.9,
127.4, 124.7, 71.4, 41.6, 29.8, 28.9. HRMS: m/z [M + Na]+ calcd
for C14H13NO4SNa: 314.0463; found: 314.0468.
1H-spiro[naphthalene-2,2′-pyrrolidine]-1,5′-dione (16):
A
solution of sulfonamide 15c (20 mg, 0.05 mmol, 1.0 equiv) in
MeCN (1.0 mL) was added at room temperature to a solution of
PhSH (16 mg, 15 μL, 150 μmol, 3.0 equiv) in MeCN (0.4 mL) con-
taining suspended K2CO3 (28 mg, 0.2 mmol, 4.0 equiv). DMSO
(0.1 mL) was then added to the reaction mixture and stirring
was continued at room temperature for 2 h, after which time
TLC showed that the reaction was complete. The reaction was
quenched with H2O (5 mL) and extracted with EtOAc (3 × 5 mL).
The combined extracts were washed with brine (5 mL), dried
(Na2SO4), and evaporated. The residue was dried under high
vacuum and purified by flash column chromatography (silica
gel; EtOAc–hexane, 3:4) to provide 16 (8 mg, 78%) as a white
solid; mp 131–133 °C. IR: 3430–3100 (br), 1698 cm–1 1H NMR
.
(300 MHz, CDCl3): δ = 8.03 (d, J = 7.6 Hz, 1 H), 7.62 (td, J = 7.6,
1.3 Hz, 1 H), 7.41 (td, J = 7.7, 0.7 Hz, 1 H), 7.30–7.29 (m, 1 H),
6.62 (d, J = 9.8 Hz, 1 H), 6.18 (d, J = 9.8 Hz, 1 H), 5.57 (br s, 1 H),
2.71–2.59 (m, 1 H), 2.46–2.31 (m, 2 H), 2.17–2.05 (m, 1 H). 13C
NMR (75.5 MHz, CDCl3): δ = 199.4, 178.8, 137.1, 135.3 (2C),
128.7, 127.9, 127.7 (2C), 127.0, 65.0, 32.2, 28.2. HRMS: m/z [M +
Na]+ calcd for C13H11NO2: 236.0687; found: 236.0687.
© Georg Thieme Verlag Stuttgart · New York — Synlett 2015, 26, 631–634