Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Unsaturated lactones Diisobutylaluminum hydride

R,4R)-Pentanediol, 237 Sulfur compounds ra-Chloroperbenzoic acid, 76 Unsaturated lactones Diisobutylaluminum hydride, 115... [Pg.386]

Many examples of natural furans are recorded as having been prepared from five-membered heterocycles such as 2(5H)-furanones (butenolides), which are reduced to furans with diisobutylaluminum hydride. The facile elimination of selenoxides derived from a-phenylseleneyl-y-lactones with formation of endocyclic a,/3-unsaturated butenolides is reported (75JOC542) as a useful route to 2,4- and 2,3,4-substituted furans via their corresponding butenolides. The mixture of dihydrofurans obtained from the tosylhydrazone of tetrahydro-2-furanone (Scheme 88) was oxidized to furans by 2,3-dichloro-5,6-dicyano-l,4-benzoquinone (66CJC1083). [Pg.692]

Reduction has been reported for other hydride reagents, such as diisobutylaluminum hydride aluminum hydride and 9-BBN-H. a,p-Unsaturated lactones are also reduced by DIBAL-H to the corresponding lactols in high yields. ... [Pg.543]

Reduction of a,p-unsaturated y-lactones to furanes (1,262). Pelletier et al. have developed a general method for conversion of 2(5H)-furanones (1) into substituted furanes (4). The method involves cycloaddition of diazoalkanes, diazo esters, and diazoketones, followed by decomposition to alkylated 2(5H)-furanones (3). The final step involves reduction with diisobutylaluminum hydride. [Pg.200]

The a,j5-unsaturated -lactone 1107 is constructed by Ghosez s methodology, which involves treating the epoxide with the lithio anion of methyl-3-phenylsulfonyl orthopropionate followed by acid hydrolysis and DBU-induced elimination. Reduction of the lactone to a lactol with diisobutylaluminum hydride and subsequent C-glycosidation furnishes aldehyde 1108 with a 4 1 epimeric ratio. This is then carried on to the desired fragment 1109. [Pg.301]


See other pages where Unsaturated lactones Diisobutylaluminum hydride is mentioned: [Pg.526]    [Pg.183]    [Pg.329]   
See also in sourсe #XX -- [ Pg.115 ]




SEARCH



Diisobutylaluminum

Diisobutylaluminum hydride

Diisobutylaluminum hydride lactones

Lactones unsaturated—

Unsaturated lactone

© 2024 chempedia.info