Danishefsky’s diene

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Its first reported synthesis was by reaction of trimethylsilyl chloride with "4-methoxy-3-buten-2-one" and zinc chloride [Preparation and Diels-Alder Reaction of a Highly Nuclerophilic Diene. Org. Synth., Coll. Vol. 7, p.312 (1990); Vol. 61, p.147 (1983). [http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=cv7p0312 Link] ] :

Its reaction with maleic anhydride is a fast one.

In a reaction with an alkene the silyl ether is a synthon for a carbonyl group through an enol while the ether group is susceptible to an elimination reaction and capable of forming a new alkene group. In addition high regioselectivity is obtained with unsymmetrical alkenes with a preference for an 1,2-relation of the ether group with the electron-deficient alkene-carbon. All this is exemplified in this Aza Diels-Alder reaction ["Asymmetric aza-Diels-Alder reaction of Danishefsky's diene with imines in a chiral reaction medium" Pegot B, Nguyen Van Buu O, Gori D, Vo-Thanh G
Beilstein Journal of Organic Chemistry, 2006 [http://bjoc.beilstein-journals.org/content/pdf/1860-5397-2-18.pdf Link] ] [This is an asymmetric reaction with a chiral ionic liquid as chiral solvent. The reported chemical yield is 66% with 60% diastereomeric excess] :

References