Lewis acid promoted reactions of [alpha],[beta]-unsaturated aldehydes and ketones with alkenes

Miscellaneous · Fri Jan 01 00:00:00 EST 1993

OSTI ID:7107530

Ali, M H

Lewis acid-Promoted reactions of methyl vinyl ketone, methoxymethyl vinyl ketone and acetoxymethyl vinyl ketone with various alkenes are reported. The enones undergo [2+2] cycloaddition reactions with various substituted styrenes to give mixtures of two cyclobutane epimers. These reactions are regioselective and the yields are high. The thermodynamically less stable cyclobutane epimers are epimerized with methanolic potassium carbonate to the thermodynamically more stable cyclobutanes. Reactions of methyl vinyl ketone, methoxymethyl vinyl ketone and acetoxymetyl vinyl ketone with methylencyclohexane promoted by mixtures of TiCl[sub 4] and Ti(O[sup i]Pr)[sub 4] in various proportions give one of more of the following products; a cyclobutane, a formal ene product and a chloro-substituted product. Reactions of acetoxymethyl vinyl ketone with cyclohexene and 1-methylcyclohexene promoted by TiCl[sub 4] give mixtures of ene and chloro-substituted products and a chloro-substituted product, respectively. The chloro-substituted products are coverted to the ene products by treating with a base or by dissolution in hot methanol. Various Lewis acid-promoted intramolecular reactions of [alpha], [beta]-unsaturated aldehydes and ketones with olefins produce formal ene products and, in one cas, a bicyclo [2.2.1] heptane product. The latter product results apparently from alkylation of the Lewis acid-bound [alpha], [beta]-unsaturated carbonyl moiety at the [beta]-carbon, rearrangement of the resultant carbocation by hydride shift, followed by coupling of the enolate and carbocation moieties. A synthesis of the natural product nanaimoal is also reported.

• Research Organization: Kansas Univ., Lawrence, KS (United States)
• OSTI ID: 7107530
• Resource Relation: Other Information: Thesis (Ph.D.)
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ALDEHYDES
CHEMICAL REACTION KINETICS
ALKENES
KETONES
LEWIS ACIDS
ORGANIC CHLORINE COMPOUNDS
TITANIUM CHLORIDES
TITANIUM OXIDES
CHALCOGENIDES
CHLORIDES
CHLORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
HYDROCARBONS
HYDROGEN COMPOUNDS
INORGANIC ACIDS
KINETICS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
REACTION KINETICS
TITANIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
400201* - Chemical & Physicochemical Properties