Abstract
The first enantioselective conjugate addition reaction of 1H -benzotriazole with a variety of enones has been developed. The process, catalyzed by a cinchona alkaloid thiourea, affords Michael adducts in good yields and with moderate to good enantioselectivities.
Key words
thioureas - enones - N-heterocycles - conjugate additions - alkaloids
References
1a
Katritzky AR.
Pozharskii AF.
Handbook of Heterocyclic Chemistry
2nd ed.:
Pergamon;
Oxford:
2002.
1b
Joule JA.
Mills K.
Heterocyclic Chemistry
4th ed.:
Blackwell Science;
Oxford:
2000.
1c
Eicher T.
Hauptmann S.
The Chemistry of Heterocycles
2nd ed.:
Wiley-VCH;
New York:
2003.
2
Purwanto MGM.
Weisz K.
Curr. Org. Chem.
2003,
7:
427
3 Triazole moieties are important pharmacophores and can be found in many drugs such as Alprazolam, a major agent for the treatment of anxiety, Fluconazole, an antifungal agent, and nucleoside-based Ribavirin, an antiviral drug. Tetrazoles have often been used as bioequivalent replacements for the carboxylic acid group (CO2 H) in pharmacologically active compounds because of their favorable physicochemical properties.
4
Perlmutter P.
Conjugate Addition Reactions in Organic Synthesis
Pergamon;
Oxford:
1992.
For recent reviews on asymmetric Michael addition reactions, see:
5a
Krause N.
Hoffmann-Röder A.
Synthesis
2001,
171
5b
Sibi M.
Manyem S.
Tetrahedron
2001,
56:
8033
5c
Berner OM.
Tedeschi L.
Enders D.
Eur. J. Org. Chem.
2002,
1877
5d
Christoffers J.
Baro A.
Angew. Chem. Int. Ed.
2003,
42:
1688
5e
Xu L.-W.
Xia C.-G.
Eur. J. Org. Chem.
2005,
633
6a
Myers JK.
Jacobsen EN.
J. Am. Chem. Soc.
1999,
121:
8959
6b
Sammis GM.
Jacobsen EN.
J. Am. Chem. Soc.
2003,
125:
4442
6c
Taylor MS.
Jacobsen EN.
J. Am. Chem. Soc.
2003,
125:
11204
6d
Vanderwal CD.
Jacobsen EN.
J. Am. Chem. Soc.
2004,
126:
14724
7
Gandelman M.
Jacobsen EN.
Angew. Chem. Int. Ed.
2005,
44:
2393
8a
Sibi MP.
Shay JJ.
Liu M.
Jasperse CP.
J. Am. Chem. Soc.
1998,
120:
6615
8b
Sibi MP.
Prabagaran N.
Ghorpades SG.
Jasperse CP.
J. Am. Chem. Soc.
2003,
125:
11796
For other selected examples, see:
8c
Fadini L.
Togni A.
Chem. Commun.
2003,
30
8d
Palomo C.
Oiarbide M.
Halder R.
Kelso M.
Gómez-Bengoa E.
Garcia JM.
J. Am. Chem. Soc.
2004,
126:
9188
8e
Yamagiwa N.
Qin H.
Matunaga S.
Shibasaki M.
J. Am. Chem. Soc.
2005,
127:
13419 ; and references cited therein
9a
Miller SJ.
Acc. Chem. Res.
2004,
37:
601
9b
Guerin DJ.
Miller SJ.
J. Am. Chem. Soc.
2002,
124:
2134
9c
Hortsmann TE.
Guerin DJ.
Miller SJ.
Angew. Chem. Int. Ed.
2000,
39:
3635
9d
Guerin DJ.
Horstmann TE.
Miller SJ.
Org. Lett.
1999,
1:
1107
For S -nucleophiles, see:
10a
Wang W.
Li H.
Wang J.
Zu L.-S.
J. Am. Chem. Soc.
2006,
128:
10354
10b
Zu L.-S.
Wang J.
Li H.
Xie H.-X.
Jiang W.
Wang W.
J. Am. Chem. Soc.
2007,
129:
1036
10c
Li H.
Zu L.-S.
Xie H.-X.
Wang J.
Jiang W.
Wang W.
Org. Lett.
2007,
9:
1833
For O -nucleophiles, see:
10d
Li H.
Wang J.
E-Nunu T.
Zu L.-S.
Jiang W.
Wei S.-H.
Wang W.
Chem. Commun.
2007,
507
For N-nucleophiles, see:
10e
Li H.
Wang J.
Xie H.-X.
Zu L.-S.
Jiang W.
Duesler EN.
Wang W.
Org. Lett.
2007,
9:
965
For P-nucleophiles, see:
10f
Wang J.
Heikkinen LD.
Li H.
Zu L.-S.
Jiang W.
Xie H.-X.
Wang W.
Adv. Synth. Catal.
2007,
349:
1052
11
Chen YK.
Yishida M.
MacMillan DWC.
J. Am. Chem. Soc.
2006,
128:
9328
12a
Vesely J.
Ibrahem I.
Rios R.
Zhao G.-L.
Xu Y.
Córdova A.
Tetrahedron Lett.
2007,
48:
2193
12b
Vesely J.
Ibrahem I.
Zhao G .-L.
Rios R.
Xu Y.
Córdova A.
Angew. Chem. Int. Ed.
2007,
46:
778
13
Wang J.
Li H.
Zu L.-S.
Wang W.
Org. Lett.
2006,
8:
1391
For reviews on asymmetric catalysis by hydrogen-bonding interactions, see:
14a
Schreiner PR.
Chem. Soc. Rev.
2003,
32:
289
14b
Tian S.-K.
Chen Y.
Hang J.
Tang L.
McDaid P.
Deng L.
Acc. Chem. Res.
2004,
37:
521
14c
Takemoto Y.
Org. Biomol. Chem.
2005,
3:
4299
14d
Taylor MS.
Jacobsen EN.
Angew. Chem. Int. Ed.
2006,
45:
1520
14e
Akiyama T.
Itoh J.
Fuchibe K.
Adv. Synth. Catal.
2006,
348:
999
14f
Connon SJ.
Chem. Eur. J.
2006,
12:
5418
For examples of thiourea-catalyzed reactions, see:
15a
Curran DP.
Kuo LH.
J. Org. Chem.
1994,
59:
3259
15b
Sigman MS.
Jacobsen EN.
J. Am. Chem. Soc.
1998,
120:
4901
15c
Okino T.
Hoashi Y.
Takemoto Y.
J. Am. Chem. Soc.
2003,
125:
12672
15d
Tian S.-K.
Ran H.
Deng L.
J. Am. Chem. Soc.
2003,
125:
9900
15e
Li H.
Wang Y.
Tang L.
Wu F.
Liu X.
Guo C.
Foxman BM.
Deng L.
Angew. Chem. Int. Ed.
2005,
44:
105
15f
Vakulya B.
Varga S.
Csampai A.
Soós T.
Org. Lett.
2005,
7:
1967
15g
Berkessel A.
Cleemann F.
Mukherjee S.
Müller TN.
Lex J.
Angew. Chem. Int. Ed.
2005,
44:
807
15h
Herrera RP.
Sgarani V.
Bernardi L.
Ricci A.
Angew. Chem. Int. Ed.
2005,
44:
6567
15i
McCooey SH.
Connon SJ.
Angew. Chem. Int. Ed.
2005,
44:
6367
15j
Ye J.
Dixon DJ.
Hynes PS.
Chem. Commun.
2005,
4481
15k
Tsogoeva SB.
Wei S.
Chem. Commun.
2005,
1451
15l
Song J.
Wang Y.
Deng L.
J. Am. Chem. Soc.
2006,
128:
6048
15m
Liu T.-Y.
Cui H.-L.
Long J.
Li B.-J.
Wu Y.
Sing L.-S.
Chen Y.-C.
J. Am. Chem. Soc.
2007,
129:
1878
16a
Wang J.
Li H.
Duan W.-H.
Zu L.-S.
Wang W.
Org. Lett.
2005,
7:
4293
16b
Wang J.
Li H.
Yu X.
Zu L.
Wang W.
Org. Lett.
2005,
7:
4713
16c
Wang J.
Li H.
Zu L.-S.
Jiang W.
Wang W.
Adv. Synth. Catal.
2006,
248:
2047
16d
Wang J.
Li H.
Zu L.-S.
Jiang W.
Xie H.-X.
Duan W.-H.
Wang W.
J. Am. Chem. Soc.
2006,
128:
12652
17 CCDC 292939 contains the supplementary crystallographic data. These data can be obtained free of charge via www.ccdc.cam.ac.uk.
18
Wiley RH.
Smith NR.
Johnson DM.
Moffat J.
J. Am. Chem. Soc.
1954,
76:
4933