Abstract
Glycosylation of alcohols containing acid-sensitive groups, as
for example 1,2-5,6-di-O -isopropylidene-glucofuranose, Fmoc-threonine tert -butyl ester or farnesol, is achieved
using glycosyl trichloroacetimidates activated by gold(I)
chloride (5-10 mol%). While glycosylation with
2-O -acyl protected glycosyl donors proceeds
with 1,2-trans -selectivity, non-neighboring
group active glycosyldonors give mixtures of anomeric glycosides
or α-glycosides depending upon their structure and the
reactivity of the glycosyl acceptor.
Key words
gold catalysis - glycosylation - glycosyl halide
References and Notes
1 Spiro RG.
Glycobiology
2002,
12:
43
2a Dekker J.
Rosen JWA.
Büller HA.
Einerhand
AWC.
Trends
Biochem. Sci.
2002,
27:
126
2b Dwek
RA.
Chem. Rev.
1996,
96:
683
3 Dziadek S.
Hobel A.
Schmitt E.
Kunz H.
Angew. Chem. Int. Ed.
2005,
44:
7630
4 Kuhn A.
Kunz H.
Angew. Chem. Int. Ed.
2007,
46:
454 ; and literature cited therein
5a Zhu X.
Schmidt RR.
Angew. Chem. Int.
Ed.
2009,
48:
1900
5b Codeé DCJ.
Litjens REJN.
van den Bos LJ.
Overkleft HS.
van der Marel GA.
Chem. Soc. Rev.
2005,
34:
769
5c Manabe S.
Ito Y.
Curr. Bioact. Compd.
2008,
4:
258
6 Morales-Serna A.
Diaz J.
Matheu MI.
Castillon S.
Eur. J. Org. Chem.
2009,
23:
3849
7 Caputo R.
Kunz H.
Mastroianni D.
Palumbo G.
Petadella S.
Solla F.
Eur. J. Org. Chem.
1999,
3147
8 Mensah EA.
Nguyen HM.
J. Am. Chem. Soc.
2009,
131:
8778
9a Schmidt RR.
Michel J.
Angew.
Chem., Int. Ed. Engl.
1980,
19:
731
9b Kinzy W.
Schmidt RR.
Adv. Carbohydr. Chem.
Biochem.
1994,
50:
21
10 Vidadala SR.
Hotha S.
Chem. Commun.
2009,
2505
11 Mensah EA.
Azarelli JM.
Nguyen HM.
J. Org. Chem.
2009,
74:
1650
12 Zhang G.
Liu Q.
Shi L.
Wang J.
Tetrahedron
2008,
64:
339
13 Li Y.
Tang P.
Chen Y.
Yu B.
J.
Org. Chem.
2008,
73:
4323
14 Liebe B.
Kunz H.
Helv. Chim. Acta
1997,
80:
1473
15 Schmidt RR.
Angew.
Chem., Int. Ed. Engl.
1986,
25:
212
17 Eichler E.
Jennings HJ.
Gilbert M.
Whitfield DM.
Carbohydr. Res.
1999,
319:
1
18 Fischer E.
Helferich B.
Liebigs Ann. Chem.
1911,
383:
68
19a Iga DP.
Iga S.
Schmidt RR.
Buzas M.-C.
Carbohydr.
Res.
2005,
340:
2052
19b Kulkarni SS.
Gervay-Hague J.
Org.
Lett.
2008,
10:
4739
20 Pleuss N.
Kunz H.
Synthesis
2005,
122
16
Analytical Data
for Compounds 6, 8, and 10
6a : [α]D
²5 -38.2
(c 1, CHCl3 ). ¹ H
NMR (300 MHz, CDCl3 ): δ = 4.52 (H-1, J
1,2 = 7.7
Hz).
[¹8 6b : [α]D
²5 28.1. ¹ H
NMR (300 MHz, CDCl3 ): δ = 4.51 (H-1, J
1,2 = 8.1
Hz).8a : [α]D
²5 -5.1. ¹ H
NMR (300 MHz, CDCl3 ): δ = 4.51 (H-1, J
1,2 = 8.1
Hz).
[¹9 8b : [α]D
²5 -28.0. ¹ H
NMR (300 MHz, CDCl3 ): J
1,2 = 8.1
Hz).8c : [α]D
²5 4.4. ¹ H
NMR (300 MHz, CDCl3 ): δ = 4.46 (H-1, J
1,2 = 7.7
Hz).8d : [α]D
²5 -6.8. ¹ H
NMR (300 MHz, CDCl3 ): δ = 4.47 (H-1, J
1,2 = 8.1
Hz).
[²0 8e , β-anomer: [α]D
²5 11.3. ¹ H
NMR (300 MHz, CDCl3 ): δ = 4.97 (H-1, J
1,2 = 8.1
Hz).8e , α-anomer: [α]D
²5 73.5. ¹ H
NMR (300 MHz, CDCl3 ): δ = 5.56-5.49
(m, 2 H, H-1, H-2). ¹³ C NMR (75.5 MHz,
CDCl3 ): δ = 95.1 (C-1).10a : [α]D
²5 25.6
(c 1, CHCl3 ). ¹ H
NMR (300 MHz, CDCl3 ): δ = 5.32 (H-1, J
1,2 = 3.7
Hz). 10b : [α]D
²5 121.5
(c 1, CHCl3 ). ¹ H
NMR (300 MHz, CDCl3 ): δ = 4.93 (H-1, J
1,2 = 3.7
Hz).
