A New Synthesis of Occidol

1999 ◽  
Vol 64 (3) ◽  
pp. 533-538 ◽  
Author(s):  
Ramchandra Bhimrao Mane ◽  
Abhijit Jaysingrao Kadam
Keyword(s):  
Sodium Borohydride ◽  
Lithium Aluminium Hydride ◽  
Borohydride Reduction ◽  
Lithium Aluminium ◽  
New Synthesis ◽  
Naphthoic Acid ◽  
Sodium Borohydride Reduction ◽  
Jones Reagent

Sodium borohydride reduction of 5,8-dimethyl-3,4-dihydronaphthalen-1-(2H)-one (4) yielded 5,8-dimethyl-1,2,3,4-tetrahydro-1-naphthol (5). The tetralol 5 on Vilsmeier-Haack reaction with N,N-dimethylacetamide yielded 1-(5,8-dimethyl-3,4-dihydro-2-naphthyl)ethan-1-one (7) which on hydrogenation over Pd/C afforded 1-(5,8-dimethyl-1,2,3,4-tetrahydro-2-naphthyl)ethan-1-one (8). The tetralol 5 on Vilsmeier-Haack formylation gave 5,8-dimethyl-3,4-dihydro-2-naphthaldehyde (9) which on reduction with lithium aluminium hydride followed by oxidation with the Jones reagent furnished 5,8-dimethyl-1,2,3,4-tetrahydro-2-naphthoic acid (11). The acid 11 on treatment with excess of methyllithium yielded (±)-occidol (1); with two moles of methyllithium it yielded ketone 8, which on reaction with methyllithium furnished (±)-occidol (1).

Flavan derivatives. XXIII. Preparation and synthetic applications of Flav-3-enes

1968 ◽  
Vol 21 (9) ◽  
pp. 2247 ◽  
Author(s):  
JW Clark-Lewis ◽  
RW Jemison
Keyword(s):  
Sodium Borohydride ◽  
Acidic Medium ◽  
Catalytic Reduction ◽  
Heterocyclic Ring ◽  
High Yield ◽  
Lithium Aluminium Hydride ◽  
Lower Field ◽  
Field Characteristic ◽  
Lithium Aluminium ◽  
New Synthesis

2'-Hydroxychalcones and α-alkoxy-2'-hydroxychalcones are converted by sodium borohydride in isopropanol into flav-3-enes and 3-alkoxyflav-3-enes in the convenient new synthesis which makes these flavenes readily available. Catalytic reduction of the flavenes gives the corresponding flavans or 3-alkoxyflavans in high yield, and the latter are obtained mainly in the 2,s-cis-form. The flavenes immediately give flavs lium cations in the cold when treated with acids in air, and oxidation of 5,7,3',4'-tetramethoxyflav-3-ene with benzoquinone in an acidic medium gave the flavylium salt, isolated as the ferrichloride. Reduction of 5,7,3',4'-tetramethoxy-flavylium chloride with lithium aluminium hydride gave 5,7,3',4'-tetramethoxy-flav-2-ene identical with the flavene obtained from (-)-epicatechin tetramethyl ether, and confirms an earlier investigation by Gramshaw, Johnson, and King. In its N.M.R. spectrum the heterocyclic-ring protons of this flav-2-ene give an ABX multiplet which is easily distinguished from the ABX multiplet at much lower field characteristic of flav-3-enes.

1,2-Benzothiazines. II. The Preparation and Sodium Borohydride Reduction of 3-Acyl-2H-1,2-benzothiazin-4(3H)-one 1,1-Dioxides1

1965 ◽  
Vol 30 (7) ◽  
pp. 2241-2246 ◽  
Author(s):  
Harold Zinnes ◽  
Roger A. Comes ◽  
Francis R. Zuleski ◽  
Albert N. Caro ◽  
John Shavel
Keyword(s):  
Sodium Borohydride ◽  
Borohydride Reduction ◽  
Sodium Borohydride Reduction
Sign in / Sign up

Export Citation Format

Share Document