ANOMALOUS RING CLEAVAGE DURING LITHIUM ALUMINUM HYDRIDE – ALUMINUM CHLORIDE REDUCTION OF 2,2,4,4-TETRAALKYLATED-1,3-DIOXOLANES

1964 ◽  
Vol 42 (5) ◽  
pp. 1005-1008 ◽  
Author(s):  
B. E. Leggetter ◽  
R. K. Brown
Keyword(s):  
Aluminum Chloride ◽  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Reductive Cleavage ◽  
Ring Cleavage ◽  
Lithium Aluminum ◽  
Ether Solution

The anomalous reductive cleavage by LiAlH4–AlCl3 of 2,2,4,4-tetramethyl-1,3-dioxolane in ether solution has been examined. Evidence supports the view that this unexpected direction of ring cleavage is due to steric repression of the formation of the intermediate oxocarbonium leading to cleavage of the C2—O1 bond of the dioxolane ring.

THE REDUCTIVE CLEAVAGE OF 1,3-OXATHIOLANES WITH LITHIUM ALUMINUM HYDRIDE IN THE PRESENCE OF ALUMINUM CHLORIDE OR BORON TRIFLUORIDE

1963 ◽  
Vol 41 (10) ◽  
pp. 2671-2682 ◽  
Author(s):  
B. E. Leggetter ◽  
R. K. Brown
Keyword(s):  
Aluminum Chloride ◽  
Lewis Acids ◽  
Chloride Solution ◽  
Boron Trifluoride ◽  
Lithium Aluminum Hydride ◽  
Methylene Chloride ◽  
Aluminum Hydride ◽  
Lithium Aluminum ◽  
Methylene Chloride Solution ◽  
Ether Solution

A number of 1,3-oxathiolanes and 1,3-dithiolanes were subjected to reduction in ether solution by lithium aluminum hydride in the presence of either aluminum chloride or boron trifluoride. Both of these Lewis acids not only isomerized 1,3-oxathiolanes but also catalyzed their hydrogenolysis to the hydroxy thioethers. Under the same conditions neither aluminum chloride nor boron trifluoride had any effect upon 1,3-dithiolanes. However, in methylene chloride solution, 1,3-dithiolanes are isomerized by both Lewis acids although their hydrogenolysis was not achieved, probably due to the insolubility of the hydride in methylene chloride.A mechanistic interpretation is discussed to explain the results obtained.

THE SYNTHESIS OF SOME INDOLYLALKYLAMINOALCOHOLS

1960 ◽  
Vol 38 (9) ◽  
pp. 1434-1438 ◽  
Author(s):  
Gerassimos Frangatos ◽  
Geza Kohan ◽  
Francis L. Chubb
Keyword(s):  
Lithium Aluminum Hydride ◽  
Aluminum Hydride ◽  
Reductive Cleavage ◽  
Lithium Aluminum ◽  
Carbonyl Groups ◽  
Open Chain ◽  
Hydride Reduction

A series of 3-indolylalkylaminoalcohols have been obtained from the lithium aluminum hydride reduction of the amides prepared by the reaction of 3-indoleglyoxylyl chloride and 2-methyl-3-indoleglyoxylyl chloride with primary aminoalcohols. When acetone was used as solvent in the reaction of 3-indoleglyoxylyis chloride and either 2-aminoethanol or 3-aminopropanol, the solvent participated in the reaction resulting in the formation of 2,2-dimethyl-3-(3-indoleglyoxyl)oxazolidine and 2,2-dimethyl-3-(3-indoleglyoxyl)tetrahydro-1,3-oxazine respectively. When the latter two compounds were reduced by lithium aluminum hydride, both carbonyl groups were completely reduced and reductive cleavage of the oxazolidine and tetrahydro-1,3-oxazine rings occurred to form the corresponding open-chain alcohols.

Sign in / Sign up

Export Citation Format

Share Document