Reaction of O-allyl glucose with [(Ph3P)2RhCl]2: an intramolecular H2 transfer

✍ Scribed by Kevin P Gable

• Book ID: 104212798
• Publisher: Elsevier Science
• Year: 1991
• Tongue: French
• Weight: 253 KB
• Volume: 32
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)71208-1

✦ Synopsis

Reaction of 3-O-ally1 glucose with [(Ph,P),KhCl], at temperatures below 60°C leads to isomerization of the double bond to form a vinyl ether. Reaction at temperatures above 100°C in N-methylpyrrolidone leads to formation of propyl and propenyl glucono-[ 1,41-lactone derivatives, identified as 'their triacetates, as well as to a decarbonylated product. The transition metal chemistry of carbohydrates has received recent attention1~3J4 due to the ready availability of such substrates, their high degree of functionality and stereogenic nature. The recent report of Andrews and Klaeren' that aldoses are decarbonylated with Wilkinson's catalyst ((ph3P)3Rhc1) led us to investigate O-ally1 glucose as a potential substrate for rhodium-catalyzed hydroacylation.5 3-O-Ally1 glucose was made in two steps from 1,2:5,6 diisopropylidene D-glucose6 as a mixture of a and B anomers (Eq. 1). The fi form may be recrystallized from methanol/chloroform,7 but in D,O the anomers equilibrate in four hours.