TY - JOUR
T1 - Fragmentation of carbohydrate anomeric alkoxyl radicals. A new synthesis of chiral 1-halo-1-iodo alditols
AU - Gonzalez, C.C.
AU - Kennedy, A.R.
AU - Leon, E.I.
AU - Riesco-Fagundo, C.
AU - Suarez, E.
N1 - Related item: http://strathprints.strath.ac.uk/1242/ Non-duplicate
PY - 2003/12/5
Y1 - 2003/12/5
N2 - Treatment of 1,2-fluorohydrins, 1,2-chlorohydrins, 1,2-bromohydrins, and 1,2-iodohydrins of the D-gluco, D-galacto, D-lacto, L-rhamno, D-allo, L-arabino, 3-deoxy-D-gluco, and 3,4-dideoxy-D-gluco families of carbohydrates with the (diacetoxyiodo)benzene/iodine system afforded 1-fluoro-1-iodo, 1-chloro-1-iodo, 1-bromo-1-iodo, and 1,1-diiodo alditols, respectively, in excellent yields. The reaction was achieved by radical fragmentation of the C1C2 bond, triggered by the initially formed anomeric alkoxy radical, and subsequent trapping of the C2-radical by iodine atoms. This methodology is compatible with the stability of the protective groups most frequently used in carbohydrate chemistry. The potential utility of these 1-halo-1-iodo alditols as chiral synthons was evaluated by their transformation into alk-1-enyl iodides and in the Takai E-olefination reaction.
AB - Treatment of 1,2-fluorohydrins, 1,2-chlorohydrins, 1,2-bromohydrins, and 1,2-iodohydrins of the D-gluco, D-galacto, D-lacto, L-rhamno, D-allo, L-arabino, 3-deoxy-D-gluco, and 3,4-dideoxy-D-gluco families of carbohydrates with the (diacetoxyiodo)benzene/iodine system afforded 1-fluoro-1-iodo, 1-chloro-1-iodo, 1-bromo-1-iodo, and 1,1-diiodo alditols, respectively, in excellent yields. The reaction was achieved by radical fragmentation of the C1C2 bond, triggered by the initially formed anomeric alkoxy radical, and subsequent trapping of the C2-radical by iodine atoms. This methodology is compatible with the stability of the protective groups most frequently used in carbohydrate chemistry. The potential utility of these 1-halo-1-iodo alditols as chiral synthons was evaluated by their transformation into alk-1-enyl iodides and in the Takai E-olefination reaction.
KW - halogen compounds
KW - alditols
KW - carbohydrates
KW - iodine
KW - radical reactions
UR - http://strathprints.strath.ac.uk/1242/
U2 - 10.1002/chem.200305294
DO - 10.1002/chem.200305294
M3 - Article
SN - 0947-6539
VL - 9
SP - 5800
EP - 5809
JO - Chemistry - A European Journal
JF - Chemistry - A European Journal
IS - 23
ER -