Synthesis of an intensely sweet chlorodeoxysucrose: Mechanism of 4′-chlorination of sucrose by sulphuryl chloride
作者:Cheang Kuan Lee
DOI:10.1016/0008-6215(87)80200-8
日期:1987.4
Abstract Reaction of 6- O -acetylsucrose 1 with sulphuryl chloride in chloroform-pyridine affords, after dechlorosulphation and acetylation, a mixture of two isomeric 2,3,6-tri- O -acetyl-4-chloro-4-deoxy-α- d -galactopyranosyl 3- O -acetyl-1,4,6-trichloro-1,4,6-trideoxy-β- d -hexulofuranosides ( 6 and 7 ) and 2,3,6-tri- O -acetyl-4-chloro-4-deoxy-α- d -galactopyranosyl 3,4-di- O -acetyl-1,6-dichloro-1
摘要6-O-乙酰基蔗糖1与硫酰氯在氯仿-吡啶中反应,经脱氯硫化和乙酰化后,得到两种异构体2,3,6-三-O-乙酰基-4-氯-4-脱氧-α-的混合物d-吡喃半乳糖苷3- O-乙酰基1,4,6-三氯-1,4,6-丁氧基-β-d-六呋喃呋喃糖苷(6和7)和2,3,6-三-O-乙酰基-4-氯-4-脱氧-α-d-吡喃半乳糖苷3,4-二-O-乙酰基-1,6-二氯-1,6-二脱氧-β-d-果糖呋喃糖苷(4)。C-4,C-1'和C-6'的氯化反应是通过氯离子将最初形成的氯磺酰氧基直接置换而发生的,但4'-氯硫酸酯的置换在空间上受阻。4'-氯取代基的引入涉及中间体3',4'-环氧化物通过氯离子的开环,核糖-环氧化物产生山梨醇-异构体6,而Lyxo-环氧化物产生果糖-异构体7。