Abstract
A mild and efficient Mitsunobu protocol for the regioselective
alkylation of catechols such as 3,4-dihydroxybenzaldehyde and methyl
3,4-dihydroxybenzoate is described. The para -alkylation
products could be easily prepared via the Mitsunobu reaction with
high selectivity in moderate to good yields.
Key words
regioselective alkylation - Mitsunobu reaction - catechol - 3,4-dihydroxybenzaldehyde - different acidity
References and Notes
1a Gu W.-X.
Jing X.-B.
Pan X.-F.
Chan ASC.
Yang T.-K.
Tetrahedron Lett.
2000,
41:
6079
1b Banwell MG.
Chand S.
Savage GP.
Tetrahedron: Asymmetry
2005,
16:
1645
1c Reitz A.
Avery MA.
Verlander MS.
Goodman M.
J. Org.
Chem.
1981,
46:
4859
1d Desroses M.
Laconde G.
Depredux P.
Hénichart J.-P.
Org. Prep. Proced.
Int.
2004,
36:
445
1e Pederson AMP.
Ward
EM.
Schoonover DV.
Slebodnick C.
Gibson HW.
1f Meuzelaar GJ.
van Vliet MCA.
Maat L.
Sheldon RA.
Eur.
J. Org. Chem.
1999,
2315
2a Wymann WE.
Davis R.
Patterson JW.
Pfister JR.
Synth. Commun.
1988,
18:
1379
2b Kessar SV.
Gupta YP.
Mohammad T.
Goyal M.
Sawal KK.
2c Hegedüs B.
Helv. Chim. Acta
1963,
2604
2d Hänsel R.
Su T.-L.
Schulz J.
Chem.
Ber.
1977,
110:
3664
2e Plourde GL.
Spaetzel RR.
Molecules
2002,
7:
697
2f He C.-L.
Shi Z.-M.
Zhou Q.-Z.
Li S.-J.
Li N.
Huang F.-H.
J. Org. Chem.
2008,
73:
5872
2g Orchard MG, Neuss JC, and Galley CMS. inventors; Patent US 7105554B2.
3a Mitsunobu O.
Synthesis
1981,
1
3b Nune SK.
Synlett
2003,
1221
3c Kumara Swamy KC.
Bhuvan Kumar
NN.
Balaraman E.
Pavan Kumar KVP.
Chem. Rev.
2009,
109:
2551
4a Manivel P.
Rai NP.
Jayashankara VP.
Arunachalam PN.
Tetrahedron Lett.
2007,
48:
2701
4b Caras-Quintero D.
Bäuerle P.
Chem.
Commun.
2002,
2690
4c Cao X.-P.
Tetrahedron
2002,
58:
1301
4d Cao X.-P.
Chan T.-L.
Chow H.-F.
Tu J.
J. Chem. Soc., Chem. Commun.
1995,
1297
4e Brosse N.
Pinto MF.
Bodiguel J.
Jamart-Grégoire B.
J. Org. Chem.
2001,
66:
2869
4f Holub N.
Neidhöfer J.
Blechert S.
Org.
Lett.
2005,
7:
1227
4g Hillier MC.
Desrosiers JN.
Marcoux JE.
Grabowski EJJ.
Org.
Lett.
2004,
6:
573
4h Anderson NG.
Lust DA.
Colapret KA.
Simpson JH.
Malley MF.
Gougoutas JZ.
J. Org. Chem.
1996,
61:
7955
5a Gu W.-X.
Chen X.-C.
Pan X.-F.
Chan ASC.
Yang T.-K.
Tetrahedron: Asymmetry
2000,
11:
2801
5b Kummeter M.
Kazmaier U.
Eur. J. Org. Chem.
2003,
3330
5c Tron GC.
Pagliai F.
Grosso ED.
Genazzani AA.
Sorba G.
J. Med. Chem.
2005,
48:
3260
5d Shimokawa J.
Shirai K.
Tanatani A.
Hashimoto Y.
Nagasawa K.
Angew.
Chem. Int. Ed.
2004,
43:
1559
5e Shen R.
Lin CT.
Porco JA.
J. Am. Chem. Soc.
2002,
124:
5650
6a Pautard-Cooper A.
Evans SA.
J. Org. Chem.
1988,
53:
2300
6b Pautard-Cooper A.
Evans SA.
J.
Org. Chem.
1989,
54:
2485
6c Saeed M.
Ilg T.
Schick M.
Abbas M.
Voelter W.
Tetrahedron
Lett.
2001,
42:
7401
6d Wang F.-D.
Yue J.-M.
Eur. J. Org. Chem.
2005,
2575
7 Wang G.-J.
Ella-Menye J.-R.
Martin MS.
Yang H.
Williams K.
Org.
Lett.
2008,
10:
4203
8 Tahir H.
Hindsgaul O.
J. Org. Chem.
2000,
65:
911
9 Ko SY.
J.
Org. Chem.
2002,
67:
2689
10 Ang K.-P.
Tan S.-F.
J. Chem. Soc., Perkin Trans.
2
1979,
1525
11a Wang X.-L.
Liu D.
Xia Y.-M.
Cao X.-P.
Pan X.-F.
Chin. J. Chem.
2004,
22:
467
11b Ding T.
Wang X.
Cao X.
Chin.
J. Chem.
2006,
24:
1618
12 Wang X.-L.
Li X.-D.
Xue J.-J.
Zhao Y.-L.
Zhang
Y.-M.
Tetrahedron
Lett.
2009,
50:
413
13a Kim Y.-W.
Hackett JC.
Brueggemeier RW.
J. Med. Chem.
2004,
47:
4032
13b Pettus LH.
Van De Water
RW.
Pettus TRR.
Org.
Lett.
2001,
3:
905
13c Kim
Y.-W.
Mobley JA.
Brueggemeier RW.
Bioorg. Med. Chem. Lett.
2003,
13:
1475
14
General Procedure
for the Regioselective Alkylation under Mitsunobu Conditions :
DIAD (4.5 mmol) and Ph3 P (4.5 mmol) were dissolved in
anhyd THF (20 mL), and the solution was cooled in an ice bath. Alcohol
(3 mmol) was added. After the mixture was stirred for 10 min, a
solution of catechol (3 mmol) in anhyd THF (5 mL) was added immediately.
After stirring for 30 min, the reaction mixture was warmed to r.t.
and stirred. When the reaction was judged to be complete (TLC),
the mixture was evaporated under vacuum and the residue was purified
by column chroma-tography on silica gel eluting with a mixture of
PE and EtOAc.Spectral Data for Methyl
4-Butyloxy-3-hydroxybenzoate (Table 1, Entry 10) : colorless
crystals; mp 114-115 ˚C.
¹ H
NMR (400 MHz, CDCl3 ): δ = 0.99 (t, J = 7.2 Hz, 3 H), 1.50 (m, 2
H), 1.82 (m, 2 H), 3.87 (s, 3 H), 4.10 (t, J = 6.4 Hz,
2 H), 5.71 (s, 1 H), 6.85 (d, J = 9.2
Hz, 1 H), 7.59 (m, 2 H). ¹³ C NMR (100
MHz, CDCl3 ): δ = 13.7, 19.1, 31.0,
51.9, 68.8, 110.6, 115.5, 122.7, 123.1, 145.3, 149.8, 166.8.
