Reaction of N3-benzoyl-3',5'-O-(di-tert-butylsilanediyl)uridine with hindered electrophiles: intermolecular N3 to 2'-O protecting group transfer.
The compound N3-benzoyl-3',5'-O-(di-tert-butylsilanediyl)uridine 2 was alkylated with various alkyl iodides in CH3CN in the presence of base. Normal 2'-O-alkylated products were obtained with methyl or benzyl iodide. If hindered alkyl iodides with beta-branching such as 2-ethylbutyl iodide were used as electrophiles under the same conditions, N3-alkyl-2'-O-benzoyl uridine derivatives were produced. This unexpected transformation is usually dormant with reactive alkylating agents, but expressed with sterically hindered, less reactive electrophiles. This unwanted reaction gives isomeric products whose spectra differ in only subtle ways from target compounds.
Zhu
Lei
L
Department of Chemistry, New York University, New York, NY 10003, USA.
dos Santos
Osvaldo
O
Seeman
Nadrian C
NC
Canary
James W
JW
D000478:Alkylation; D001555:Benzene Derivatives / Q000737:chemistry*; D006847:Hydrocarbons, Iodinated / Q000737:chemistry; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013237:Stereoisomerism; D014529:Uridine / Q000031:analogs & derivatives* / Q000737:chemistry
D001555:Benzene Derivatives; D006847:Hydrocarbons, Iodinated; D014529:Uridine