Enones reactions

In respect of cycloreversion, cyclobutane-fused fullerenes derived from acyclic enones [342] are less stable than their bycycKc equivalents (e.g. 293, Scheme 4.55). For the addition of mesityl oxide the equilibrium constant is so small that a 1000-fold excess of the enone is necessary to complete the reaction. The product of 302 is more stable and requires only a 100-fold excess of the enone. Reaction of 302... 

Prolines.1 The complex 2 undergoes base-catalyzed (CH,ONa) Michael addition to a,p-enals and -enones. Reaction of 2 with acrolein furnishes a dihydro-pyrrole-2-carboxylic acid which is reduced to (S)-proline. 

Enone Reaction Conditions Regiomcr (%) Enone Reaction Conditions Regjomer (%) ... 

The methyl ketone at the end of the chain (3-9) can be expected to be more reactive than the ring enone. Reaction of... 

P.y-Enones. Reaction of 1,2-bis(methylenc)cyclohexane with activated magnesium provides a magnesium complex (I). This complex reacts with ethyl acetate at —10°... 

Cyclic a, fi-enones. Reaction of triisopropyl (TIPS) enol ethers of cyclic ketones with the combination of C6H5IO and trimcthylsilyl azide in CH2CI2 at -15 provides a /8-azide, which on treatment with Bu4NF at 0° is converted into the o,/8-cnone. Examples ... 

The method was applied to a series of triplet type-B bicyclic (Equation 8.4) and Type B enone reactions (Equation... 

Cyclic a, fi-enones. Reaction of triisopr with the combination of QHslO and irimeihyl /3-azide, which on treatment with BU4NF at 0... 

Reactions with D Cenophiles. Azulenes do not undergo cycloaddition reactions with dienophiles but instead they react by conjugate addition to the enone, reaction involving the 1-position of the azulene. Thus maleic anhydride gives an azulenylsuccinic anhydride [73-75] ... 

Turning to more specific strategies, Taber and Gunn have discussed the synthetic utility of enones and exemplified a useful homologation of ketones to enones [reaction (2)], via chlorosulphoxides. Danishefsky has provided an... 

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