"Super armed" glycosyl donors: conformational arming of thioglycosides by silylation

Christian Marcus Pedersen; Lars Ulrik Nordstrøm; Mikael Bols

doi:10.1021/ja071955l

"Super armed" glycosyl donors: conformational arming of thioglycosides by silylation

Christian Marcus Pedersen, Lars Ulrik Nordstrøm, Mikael Bols

132 Citationer (Scopus)

Abstract

Glycosyl donors protected with bulky silyl protective groups (tert-butyldimethylsilyl, TBS), on the 2-, 3- and 4-OH groups were found to have superior reactivity compared with benzylated thioglucosides. The enhanced reactivity is explained by the stereoelectronic effects associated with the conformational change induced by the silylation: A TBS silylated thioglucoside donor have axial OR groups while a benzylated thioglucoside have equatorial OR groups leading to much more favorable charge-dipole interactions in the transition state. This concept could be used to create ‘super armed' glucosyl, mannosyl, rhamnosyl and galactosyl donors, which could cross couple with the armed acceptors phenyl 2,3,4-tri-O-benzyl-ß-D-thioglucoside or phenyl 2,3,6-tri-O-benzyl-ß-D-thioglucoside to give the corresponding armed disaccharides in good to excellent yields.

Originalsprog	Engelsk
Tidsskrift	Journal of the American Chemical Society
Vol/bind	129
Udgave nummer	29
Sider (fra-til)	9222-9235
Antal sider	14
ISSN	0002-7863
DOI	https://doi.org/10.1021/ja071955l
Status	Udgivet - 2007
Udgivet eksternt	Ja

Adgang til dokumentet

10.1021/ja071955l

Citationsformater

@article{fc6fa750b46311dcbee902004c4f4f50,

title = "{"}Super armed{"} glycosyl donors: conformational arming of thioglycosides by silylation",

abstract = "Glycosyl donors protected with bulky silyl protective groups (tert-butyldimethylsilyl, TBS), on the 2-, 3- and 4-OH groups were found to have superior reactivity compared with benzylated thioglucosides. The enhanced reactivity is explained by the stereoelectronic effects associated with the conformational change induced by the silylation: A TBS silylated thioglucoside donor have axial OR groups while a benzylated thioglucoside have equatorial OR groups leading to much more favorable charge-dipole interactions in the transition state. This concept could be used to create {\textquoteleft}super armed' glucosyl, mannosyl, rhamnosyl and galactosyl donors, which could cross couple with the armed acceptors phenyl 2,3,4-tri-O-benzyl-{\ss}-D-thioglucoside or phenyl 2,3,6-tri-O-benzyl-{\ss}-D-thioglucoside to give the corresponding armed disaccharides in good to excellent yields.",

author = "Pedersen, {Christian Marcus} and Nordstr{\o}m, {Lars Ulrik} and Mikael Bols",

year = "2007",

doi = "10.1021/ja071955l",

language = "English",

volume = "129",

pages = "9222--9235",

journal = "Journal of the American Chemical Society",

issn = "0002-7863",

publisher = "ACS Publications",

number = "29",

}

TY - JOUR

T1 - "Super armed" glycosyl donors

T2 - conformational arming of thioglycosides by silylation

AU - Pedersen, Christian Marcus

AU - Nordstrøm, Lars Ulrik

AU - Bols, Mikael

PY - 2007

Y1 - 2007

N2 - Glycosyl donors protected with bulky silyl protective groups (tert-butyldimethylsilyl, TBS), on the 2-, 3- and 4-OH groups were found to have superior reactivity compared with benzylated thioglucosides. The enhanced reactivity is explained by the stereoelectronic effects associated with the conformational change induced by the silylation: A TBS silylated thioglucoside donor have axial OR groups while a benzylated thioglucoside have equatorial OR groups leading to much more favorable charge-dipole interactions in the transition state. This concept could be used to create ‘super armed' glucosyl, mannosyl, rhamnosyl and galactosyl donors, which could cross couple with the armed acceptors phenyl 2,3,4-tri-O-benzyl-ß-D-thioglucoside or phenyl 2,3,6-tri-O-benzyl-ß-D-thioglucoside to give the corresponding armed disaccharides in good to excellent yields.

AB - Glycosyl donors protected with bulky silyl protective groups (tert-butyldimethylsilyl, TBS), on the 2-, 3- and 4-OH groups were found to have superior reactivity compared with benzylated thioglucosides. The enhanced reactivity is explained by the stereoelectronic effects associated with the conformational change induced by the silylation: A TBS silylated thioglucoside donor have axial OR groups while a benzylated thioglucoside have equatorial OR groups leading to much more favorable charge-dipole interactions in the transition state. This concept could be used to create ‘super armed' glucosyl, mannosyl, rhamnosyl and galactosyl donors, which could cross couple with the armed acceptors phenyl 2,3,4-tri-O-benzyl-ß-D-thioglucoside or phenyl 2,3,6-tri-O-benzyl-ß-D-thioglucoside to give the corresponding armed disaccharides in good to excellent yields.

U2 - 10.1021/ja071955l

DO - 10.1021/ja071955l

M3 - Journal article

C2 - 17602482

SN - 0002-7863

VL - 129

SP - 9222

EP - 9235

JO - Journal of the American Chemical Society

JF - Journal of the American Chemical Society

IS - 29

ER -