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Asymmetric Diels-Alder reaction is one step in the biosynthesis of the statin lovastatin. [60] The retro-Diels–Alder reaction is used in the industrial production of cyclopentadiene. Cyclopentadiene is a precursor to various norbornenes, which are common monomers. The Diels–Alder reaction is also employed in the production of vitamin B6.
It reverts to anthracene thermally or with UV irradiation below 300 nm. Substituted anthracene derivatives behave similarly. The reaction is affected by the presence of oxygen. [23] [24] Anthracene also reacts with dienophile singlet oxygen in a [4+2]-cycloaddition (Diels–Alder reaction): Diels alder reaction of anthracene with singlet oxygen
The retro-Diels–Alder reaction (rDA reaction) is the reverse of the Diels–Alder (DA) reaction, a [4+2] cycloelimination. It involves the formation of a diene and dienophile from a cyclohexene. It can be accomplished spontaneously with heat, or with acid or base mediation. [1] [2]
The oxidation of anthracene. Chromium(VI) is the typical oxidant. The Friedel-Crafts reaction of benzene and phthalic anhydride in presence of AlCl 3. o-Benzoylbenzoic acid is an intermediate. This reaction is useful for producing substituted anthraquinones. The Diels-Alder reaction of naphthoquinone and butadiene followed by oxidative ...
Oxazolidinone auxiliaries, popularized by David A. Evans, have been applied to many stereoselective transformations, including aldol reactions, [19] alkylation reactions, [20] and Diels-Alder reactions. [21] [22] The oxazolidinones are substituted at the 4 and 5 positions. Through steric hindrance, the substituents direct the direction of ...
Depending on the substrate chosen, the HDDA reaction can be initiated thermally or by the addition of a suitable catalyst, often a transition metal. [1] [2] [4] [5] The prevailing mechanism for the thermally-initiated HDDA reaction is a [4+2] cycloaddition between a conjugated diyne (1,3-dialkyne) and an alkyne (often referred to as a diynophile in analogy to the Diels–Alder dienophile) to ...
The inverse electron demand Diels–Alder reaction, or DA INV or IEDDA [1] is an organic chemical reaction, in which two new chemical bonds and a six-membered ring are formed. It is related to the Diels–Alder reaction , but unlike the Diels–Alder (or DA) reaction, the DA INV is a cycloaddition between an electron-rich dienophile and an ...
The reaction produces the corresponding sulfine through a hetero-Diels–Alder reaction under kinetic control (≤ -60 °C), but, under thermodynamic control (≥ -40 °C), the reaction produces the corresponding sulfolene through a cheletropic reaction. The activation enthalpy for the hetero-Diels–Alder reaction is about 8 kJ/mol smaller ...