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2
General Synthetic Methods
Abbreviations
AIBN
2,2 -azobisisobutyronitrile
BSTFA bis(trimethylsilyl)trifluoroacetamide
CAN
ceric ammonium nitrate
DCC
N,N -dicyclohexylcarbodiimide
DIBALH diisobutylaluminum hydride
DMF
dimethylformamide
DMSO dimethyl sulfoxide
HMPA hexamethylphosphoric triamide
MS
molecular sieves
m-CPBA m-chloroperoxybenzoic acid
NBS
N-bromosuccinimide
NIS
N-iodosuccinimide
NMO
N-methyl-morpholine N-oxide
PCC
pyridinium chlorochromate
PDC
pyridinium dichromate
TFAA
trifluoroacetic anhydride
TEMPO 2,2,6,6-tetramethyl-1-piperidinyloxy
TPAP
tetrapropylammonium perruthenate
1 Introduction
Carbohydrates have found valuable applications as enantiomerically pure starting materials for
synthesis of non-carbohydrate compounds. Through chemical synthesis carbohydrates can be
transformed into versatile synthetic intermediates that have functional groups and stereogenic
centers structured in a framework found in many natural products, and the entire repertoire
of common reactions in organic chemistry can be performed on carbohydrates [1]. However, carbohydrates are also densely functionalized molecules and as such constitute a special
synthetic challenge. Regio- and chemoselectivity problems are frequently encountered which
often makes it necessary to protect functionalities not involved in the desired transformation. In
the following, oxidations, reductions, and deoxygenations will be discussed. An eight-volume
comprehensive encyclopedia is recommended for further information on the different reagents
for these reactions [2].
2 Oxidations
A large variety of oxidation procedures are available to the synthetic organic chemist [3]. As
presented in this chapter, many of these methods can be applied to protected carbohydrates
and some also for regioselective oxidation of unprotected or partially protected sugars.
2.1 Oxidation at the Anomeric Center
Unprotected aldoses can be selectively oxidized at the anomeric center to afford aldonic
acids/aldonolactones. This oxidation can be achieved by chemical as well as by biochemical
2
General Synthetic Methods
Abbreviations
AIBN
2,2 -azobisisobutyronitrile
BSTFA bis(trimethylsilyl)trifluoroacetamide
CAN
ceric ammonium nitrate
DCC
N,N -dicyclohexylcarbodiimide
DIBALH diisobutylaluminum hydride
DMF
dimethylformamide
DMSO dimethyl sulfoxide
HMPA hexamethylphosphoric triamide
MS
molecular sieves
m-CPBA m-chloroperoxybenzoic acid
NBS
N-bromosuccinimide
NIS
N-iodosuccinimide
NMO
N-methyl-morpholine N-oxide
PCC
pyridinium chlorochromate
PDC
pyridinium dichromate
TFAA
trifluoroacetic anhydride
TEMPO 2,2,6,6-tetramethyl-1-piperidinyloxy
TPAP
tetrapropylammonium perruthenate
1 Introduction
Carbohydrates have found valuable applications as enantiomerically pure starting materials for
synthesis of non-carbohydrate compounds. Through chemical synthesis carbohydrates can be
transformed into versatile synthetic intermediates that have functional groups and stereogenic
centers structured in a framework found in many natural products, and the entire repertoire
of common reactions in organic chemistry can be performed on carbohydrates [1]. However, carbohydrates are also densely functionalized molecules and as such constitute a special
synthetic challenge. Regio- and chemoselectivity problems are frequently encountered which
often makes it necessary to protect functionalities not involved in the desired transformation. In
the following, oxidations, reductions, and deoxygenations will be discussed. An eight-volume
comprehensive encyclopedia is recommended for further information on the different reagents
for these reactions [2].
2 Oxidations
A large variety of oxidation procedures are available to the synthetic organic chemist [3]. As
presented in this chapter, many of these methods can be applied to protected carbohydrates
and some also for regioselective oxidation of unprotected or partially protected sugars.
2.1 Oxidation at the Anomeric Center
Unprotected aldoses can be selectively oxidized at the anomeric center to afford aldonic
acids/aldonolactones. This oxidation can be achieved by chemical as well as by biochemical