References and Notes
1
Kürti L.
Czakó B.
Strategic Applications
of Named Reactions in Organic Synthesis, Background and Detailed Mechanism
Elsevier
Academic Press;
San Diego:
2005.
p.218
For reviews, see:
2a
Moriarty RM.
J. Org. Chem.
2005,
70:
2893
2b
Togo H.
Katohgi M.
Synlett
2001,
565
3
Camps P.
Lukach AE.
Pujol X.
Vázquez S.
Tetrahedron
2000,
56:
2703
4
Koo B.-S.
Kim E.-H.
Lee K.-J.
Synth.
Commun.
2002,
32:
2275
For reviews, see:
5a
Gribble GW.
Prog. Chem. Org. Nat. Prod.
2010,
91:
1
5b
Gribble GW.
Environ. Sci. Pollut. Res.
2000,
7:
37
5c
Gribble GW.
Chem. Soc. Rev.
1999,
28:
335
5d
Gribble GW.
Acc. Chem. Res.
1998,
31:
141
5e
Alvarez M.
Salas M.
Joule JA.
Heterocycles
1991,
32:
1391
6
Maruya KA.
Chemosphere
2003,
52:
409
7a
Vairappan CS.
Kawamoto T.
Miwa H.
Suzuki M.
Planta
Med.
2004,
70:
1087
7b
Carter GT.
Rinehart KL.
Li LH.
Kuentzel SL.
Connor JL.
Tetrahedron Lett.
1978,
4479
8a
Hodder AR.
Capon RJ.
J. Nat. Prod.
1991,
54:
1661
8b
Norton RS.
Wells RJ.
J.
Am. Chem. Soc.
1982,
104:
3628
9
Brennan MR.
Erickson KL.
Tetrahedron Lett.
1978,
1637
10
Putey A.
Popowycz F.
Joseph B.
Synlett
2007,
419
11
Umemoto H.
Umemoto M.
Ohta C.
Dohshita M.
Tanaka H.
Hattori S.
Hamamoto H.
Miki Y.
Heterocycles
2009,
78:
2845
12
Wirth T.
Hypervalent
Iodine Chemistry, Modern Developments in Organic Synthesis
Springer;
Berlin/Heidelberg:
2003.
13
Miki Y.
Hachiken H.
Yoshikawa I.
Heterocycles
1997,
45:
1143
14
Braddock DC.
Cansell G.
Hermitage SA.
Synlett
2004,
461
15
Conway SC.
Gribble GW.
Heterocycles
1992,
34:
2095
16a
Liu Y.
Gribble GW.
Tetrahedron
Lett.
2001,
42:
2949
16b
Baiocchi L.
Giannangeli M.
J. Heterocycl. Chem.
1988,
25:
1905
17
Liu Y.
Gribble GW.
Tetrahedron Lett.
2002,
43:
7135
18a
Janda M.
Srogl J.
Holy P.
Coll. Czech. Commun.
1981,
46:
3278
18b
Moriconi EJ.
Murray JJ.
J.
Org. Chem.
1964,
29:
3577
19a
Bergman J.
Venemalm L.
J.
Org. Chem.
1992,
57:
2495
19b
Saulnier MG.
Gribble GW.
J.
Org. Chem.
1982,
47:
757
20
Ezquerra J.
Pedregal C.
Lamas C.
Barluenga J.
Pérez M.
Garcia-Martín MA.
González JM.
J. Org. Chem.
1996,
61:
5804
21a
Kellie AE.
O’Sullivan DG.
Sadler PW.
J.
Chem. Soc.
1956,
3809
21b
Hantzsch A.
Ber.
Dtsch. Chem. Ges.
1921,
54:
1221
22
Typical Procedure
for the Decarboxylative Halogenation of Indole-2,3-dicarboxylic
Acid(1) with PIDA in the Presence of Lithium Halide
To
a mixture of PIDA and lithium halide in THF (10 mL) was added indolecarboxylic
acids 1, 6, 7 (1 mmol) at r.t., and then the reaction
mixture was stirred. H2O was added to the reaction mixture,
and the mixture was extracted with CH2Cl2.
The combined extracts were washed with 2-3% Na2S2O3 solution,
then H2O, and dried over Na2SO4.
The extracts were concentrated under reduced pressure to give a solid,
which was purified by column chromatography on silica gel to afford
the 3-halogenoindole-2-carboxylic acids(2),
2,3-dihalogenoindoles 3, 8,
and 3,3-dihalogeno-oxindoles 4, 9.
1-Phenylsulfonyl-3-bromoindole-2-carboxylic
Acid (2a)
Mp 124-125 ˚C. IR (mull): ν = 2856,
2585, 1697 cm-¹. ¹H NMR
(400 MHz, DMSO-d
6): δ = 7.24-7.36
(3 H, m), 7.50-7.68 (3 H, m), 7.91 (1 H, dd, J = 8.0, 1.5
Hz), 8.25-8.32 (2 H, m). HRMS (EI): m/z calcd
for C15H11NSO4Br2S: 379.9592;
found: 379.9602.
1-Phenylsulfonyl-2,3-dibromoindole
(3a)
Mp 143 ˚C (lit.¹5 mp
141-143 ˚C). ¹H NMR (400 MHz, CDCl3): δ = 7.22-7.40
(5 H, m), 7.46-7.54 (1 H, m), 7.78-7.84 (2 H,
m), 8.19-8.25 (1 H, m).
3-Bromo-1-methylindole-2-carboxylic
Acid (2b)
Mp 184-186 ˚C [lit.¹7 mp
180 ˚C (dec)]. IR (KBr): ν = 1671 cm-¹. ¹H
NMR (400 MHz, DMSO-d
6): δ = 3.99
(3 H, s, CH3), 7.22 (1 H, t, J = 8.0
Hz, H-5 or H-6), 7.40 (1 H, t, J = 8.0
Hz, H-6 or H-5), 7.54 (1 H, d, J = 8.0
Hz, H-4 or H-7), 7.62 (1 H, d, J = 8.0
Hz, H-7 or H-4).
3,3-Dibromo-1-methyloxindole
(4b)
Mp 202-204 ˚C (lit.¹8 mp
204-205 ˚C). IR (CHCl3): ν = 1737
cm-¹. ¹H NMR (400
MHz, DMSO-d
6): δ = 3.26
(3 H, s, CH3), 6.86 (1 H, d, J = 8.0
Hz, H-4 or H-7), 7.17 (1 H, dt, J = 8.0,
1.5 Hz, H-5 or H-6), 7.34 (1 H, dt, J = 8.0,
1.5 Hz, H-6 or H-5), 7.62 (1 H, dd, J = 8.0,
1.5 Hz, H-7 or H-4).
¹³C
NMR (100 MHz, DMSO-d
6): δ = 169.16,
139.64, 131.87, 130.37, 125.38, 124.05, 110.08, 45.28, 27.03. HRMS
(EI): m/z calcd for C9H7NOBr2:
302.8895; found: 302.8883.
1-Phenylsulfonyl-2,3-dichloroindole
(8a)
Mp 122 ˚C. ¹H NMR
(400 MHz, CDCl3): δ = 7.30-7.63
(6 H, m), 7.84-7.92 (2 H, m), 8.28 (1 H, br d, J = 8.0 Hz,
H-7 or H-4). ¹³C NMR (100 MHz, DMSO-d
6): δ = 137.59, 134.70,
134.40, 129.30, 126.94, 126.54, 126.14, 124.57, 121.24, 118.15,
114.98, 113.78. HRMS (EI): m/z calcd
for C14H9NO2Cl2S: 324.9677;
found: 324.9737.
1-Phenylsulfonyl-2,3-diiodoindole
(8b)
Mp 165-167 ˚C (lit.¹9 mp
166-167 ˚C). ¹H NMR (400 MHz, CDCl3): δ = 7.25-7.60
(6 H, m), 7.90 (2 H, br d, J = 8.0
Hz), 8.28 (1 H, br d, J = 8.0
Hz, H-7).
2,3-Diiodo-1-methylindole
(8c)
Mp 76-77 ˚C (lit.²0 mp
76-78 ˚C). ¹H NMR (400 MHz, CDCl3): δ = 3.89
(3 H, s, CH3), 7.10-7.42 (4 H, m). ¹³C NMR
(100 MHz, DMSO-d
6): δ = 138.11,
131.15, 122.71, 120.80, 120.50, 111.06, 99.78, 71.72, 36.09. HRMS
(EI):
m/z calcd for
C9H7NI2: 382.8668; found: 382.8671.
3,3-Dichloro-1-methyloxindole (9)
Mp
144-147 ˚C (lit.²¹ 143 ˚C).
IR (KBr): ν = 1740 cm-¹. ¹H NMR
(400 MHz, CDCl3): δ = 3.25 (3 H, s,
CH3), 6.85 (1 H, d, J = 8.0
Hz, H-4 or H-7), 7.17 (1 H, t, J = 8.0
Hz, H-5 or H-6), 7.39 (1 H, t, J = 8.0,
1.5 Hz, H-6 or H-5), 7.61 (1 H, d, J = 8.0
Hz, H-7 or H-4). ¹³C NMR (100 MHz,
CDCl3): δ = 168.80, 140.58, 131.85,
129.16, 125.13, 124.70, 124.14, 109.08, 26.98.