Acids dienes

Sharpless asymmetric dihydroxylation procedure was applied to the synthesis of the side chain of azinomycin A (equation 26)43. Horner-Emmons condensation of phospho-nate 36 with a /J-aziridine substituted acrolein afforded dehydroamino acid diene 37. Treatment of the diene with catalytic amounts of an osmium reagent and dihydroquini-dine (DHQD) p-chlorobenzoate resulted in asymmetric dihydroxylation, producing diol 38. Diol 38 was further converted to the naphthyl ester. 

CHC13 CC14 acid diene acid carpane ... 

Monoene fatty acids Diene fatty acids Polyene fatty acids ... 

The 2,4-dialkoxy-l.l-difluoro-l,3-diene 11 undergoes [4-f 2]-cycloaddition reactions with aldehydes in the presence of Lewis acids. Dienes with a greater number of fluorine atoms tend to be less reactive and [2 -F 2]-cycloaddition reactions can predominate for example, 1,1,4,4-tetrafluorobuta-1,3-diene preferentially undergoes [2 -F 2]-cycloaddition reactions (see Section... 

In principle, any functionality capable of producing a carbenium ion under strongly acidic conditions will be able to participate in a Ritter-type reaction. Such classes of compounds include alcohols, aldehydes, alkanes, alkenes, alkyl halides, carboxylic acids, dienes, epoxides, esters, ethers, glycols, ketones, IV-methylolamides and oximes. Consequently, an enormous number of examples is reported and only a representative selection can be presented here. A comprehensive listing of examples reported up to 1966 is provided in the review by Krimen and Cota. ... 

The second important reaction is the Acidic Diene Metathesis Polymerization — ADMET. The overall equation is as follows ... 

Scheme 3 depicts, for anacardic acid diene, the synthesis of H, by the alkylation method with a Q4 halide and the synthesis of co-hydroxy C14 the side-chains for the 8,11-diene and its stereoisomers namely (A) 7Z,10Z, (B) 7Z,10E, (C) 7E,10E and (D) 7E,10Z.. The 1-iodo derivatives of each were obtained as for route (a). This methodology has been applied to the synthesis of Fig (2)-3, anacardic acid 8(Z),ll(Z),14-triene as shown in Scheme 4. Strategies for obtaining side-chains for the stereoisomers of the triene have been described [2,114].

The Diels-AIder reaction is one of the more powerful reactions in all of organic chemistry. A Diels-AIder strategy can be used to prepare cyclic amino acids. Dienes can react with tosyl cyanide to generate lactams. Cyclopentadiene reacted with p-toluenesulfonyl cyanide (N-tosyl cyanide TsCN MeC6H4S02CN), for example, to give azabicycloheptene derivative, 7.772.100 Treatment with aqueous Tos-C ... 

Figure 4 New Rh catalysts bearing the strongly n-acidic diene, namely, tfb.

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