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29.15.1.1.2 Method 2: Synthesis from Glycosyl Halides

DOI: 10.1055/sos-SD-029-00907

Kryczka, B.; Lewkowski, J.; Zawisza, A.Science of Synthesis, (200729973.

Koenigs and Knorr first introduced the use of glycosyl halides as effective glycosyl donors in glycosylation reactions in 1903. This method is still widely employed and the anomeric stereoselectivity involved is normally determined through neighboring-group participation, as in the construction of 1,2-trans-glycosides. The classical method uses heavy-metal salts (mainly silver and mercury salts) as activating reagents and some examples of such procedures are shown in Schemes 3, 4, and 5, which summarize the syntheses of 1-O-methyl glycosides 12, 14, and 16 from glycosyl bromides 11,[‌11‌‌17‌] chlorides 13,[‌18‌‌21‌] and fluorides 15,[‌22‌‌24‌] respectively.

Meeeee 8 Meeeeeeee ee 8-M-Meeeee Meeeeeeeee eeee Meeeeeee Meeeeeee[‌88‌‌88‌]

Meeeeeeeeee 8

Meeee ­Meeeee M8 M8 M8 M8 Meeeeeeeee Meeeee Meeeee Meeee (%) Mee
α-M-eeee MMe MMe MMe MMe Me8M, 8.8e β 88 [‌88‌]
α-M-eeeee MM8MMe MMe MMe MMMM8MM8MM=MM8 Me(MM)8, ee, 8e β 88 [‌88‌]
α-M-eeeee MM8MMe MMe MMe MMe Me(MM)8 β 88 [‌88‌]
α-M-eeeee MM8MMe MMe MMe MMe MeMe8, 8-Å eeeeeeeee eeeeee, 88°M, 8e β 88 [‌88‌]
α-M-eeeee MM8MMe MMe MMe MMM8Me MeMMe, 8,8,8-eeeeeeeee, 88°M β 88 [‌88‌]
α-M-eeeee MM8MMe MMe MMe M8 Me8MeM8, 8-Å eeeeeeeee eeeeee, 88°M, 8e β 88 [‌88‌]
α-M-eeeeeee MM8MMe MMe MMe MMe MeMM8, MeMM, 8,8,8-eeeeeeeee α/β 8/88 [‌88‌]
α-M-eeeee MM8MMe MMe MMe MMMM8Me MeMM β 88 [‌88‌]

Meeeee 8 Meeeeeeee ee 8-M-Meeeee Meeeeeeeee eeee Meeeeeee Meeeeeeee[‌88‌‌88‌]

Meeeeeeeeee 8

Meeee ­Meeeee M8 M8 M8 M8 Meeeeeeeee Meeeee Meeeee Meeee (%) Mee
α-M-eeeee MM8MMe MMe MMe MMMe Me8MM8, MeMM8 β 88 [‌88‌]
α-M-eeeee MM8MMe MMe MMe MMMMM Me(MMe)8, 8-Å eeeeeeeee eeeeee, ee, 88e β 88 [‌88‌]
α-M-eeeee MM8MMe MMe MMe MMMe Me(MMe)8, 8,8,8,8-eeeeeee­eeeeeeee, 8-Å eeeeeeeee eeeeee, ee, 8e e 88 [‌88‌]
α-M-eeeee MM8MMe MMe MMe MMMe MeMMe, ee, 88eee β 88 [‌88‌]

e Mee eeeeeeee.

Meeeee 8 Meeeeeeee ee 8-M-Meeeee Meeeeeeeee eeee Meeeeeee Meeeeeeee[‌88‌‌88‌]

Meeeeeeeeee 8

Meeee Meeeee M8 M8 M8 M8 Meeeeeeeee Meeeee Meeeee Meeee (%) Mee
α-M-eeeeeee MM8MM MM MM M MMe, eeee, 8e β 88 [‌88‌]
α-M-eeeee MM8MM MM MM MMMe MeM8, 8-Å eeeeeeeee eeeeee, MeMM, ee, 88e e 88 [‌88‌]
β-M-eeeee MM8MM MM MM MM Me-Meeeeeeee 88, ee α 88 [‌88‌]
α-M-eeeee MM8MM MM MM MM Me-Meeeeeeee 88, ee β 88 [‌88‌]

e Mee eeeeeeee.

Meeeeeeeeeee Meeeeeeee

Meeeee 8,8,8-Mee-M-eeeeee-8-eeeeeee-β-M-eeeeeeeeeeeeee (β-M-eeee-88, M8=MMe; M8=M8=M8=MMe); Meeeeee Meeeeeeee:[‌88‌]

Mee eeeeeeeeeeeee eeeeeee M-eeee-88 (M8=MMe; M8=M8=M8=MMe; 8.8e) ee MeMM/MMMe8 (8:8; 8eM) eee eeeeeee eeee Me8M (8.8e) eee 8.8e, eee eee eeee eee eeee eeeeeee eeee eeeeeeeee eeeeeeee. Meeeeee ee eee eeeeeee eeee e eeeeeee, eeeee eee eeeeeeeeee eeee MeMM/M8M (8:8); eeeee: 8.88e (88%); ee 888888°M.

Meeeee 8,8,8-Mee-M-eeeeee-8-eeeee-8-(eeeeeeeeeee)-β-M-eeeeeeeeeeeeeee (β-M-eeeee-88, M8=MM8MMe; M8=M8=MMe; M8=MMMMM); Meeeeee Meeeeeeee:[‌88‌]

Me(MMe)8 (888ee, 8.8eeee) eee eeeee ee e eeeeeee ee eee eeeeeeeeeeeeee eeeeeeee M-eeeee-88 (M8=MM8MMe; M8=M8=MMe; M8=MMMMM; 888ee, 8.8eeee), eeeee MeMM (8.8eM), eee eeeeeeeee eeeeeeee 8-Å eeeeeeeee eeeeee (888ee) ee eeeee MM8Me8 (8eM) ee 8°M. Mee eeeeeee eee eeeeeee ee ee eeeee eeeee eee 88e, eeee eeeeeeeeeee eeee eee. ee MeMMM8 (8eM), eee eeeeeeee. Mee eeeeeee eeeee eee eeeeeeeee eee eeeeeeeeeeee, eee eee eeeeeee eee eeeeeeee ee eeeeee eeeeeeeeeeeeee (eeeeee eee, eeeeee/eeeeeee 8:8); eeeee: 888ee (88%); ee 888888°M (eeeeee/eeeeeee), [α]M 88 (e 8, MMMe8).

Meeeee β-M-Meeeeeeeeeeeeee (β-M-eeeee-88, M8=MM8MM; M8=M8=M8=MM); Meeeeee Meeeeeeee:[‌88‌]

Me-Meeeeeeee 88 (888ee) eee eeeeeeee ee MeMM (8eM) eee α-eeeeeeee eeeeeeee α-M-eeeee-88 (M8=MM8MM; M8=M8=M8=MM; 88ee, 8.88eeee) eee eeeee. Mee eeeeeee eee eeeeeee ee ee eeeee eee eeeeeeee eeeeeeee eee eeeeeeeeeee (MMM). Mee eeeee eee eeeeeee ee eeeeeeeeee eee eeeeee eeee MeMM, eee eee eeeeeeee eee eeeeeeeeeeee eeeee eeeeeee eeeeeeee ee eeee e eeeeeee, eeeee eee eeeeeeeeeeeeeee (eeeeee eee, MeMMe/MeMM 8:8); eeeee: 88ee (88%).

References