@article{pittir19475,
          volume = {7},
          number = {1},
           month = {January},
          author = {S Manku and DP Curran},
           title = {Fluorous mixture synthesis of 4-alkylidene cyclopentenones via a rhodium-catalyzed [2+2+1] cycloaddition of alkynyl allenes},
         journal = {Journal of Combinatorial Chemistry},
           pages = {63 -- 68},
            year = {2005},
             url = {http://d-scholarship-dev.library.pitt.edu/19475/},
        abstract = {Fluorous mixture synthesis was used to prepare a library of 4-alkylidene cyclopentenones starting from a mixture of four {\ensuremath{\alpha}}-amino acid derivatives tagged with different fluorous benzyl carbamates (FCBz) of varying fluorine content. The amino acids were converted to the corresponding propargyl esters and then subjected to an ester-enolate Claisen rearrangement to give a mixture of allenic amino esters. The allenes were then split four ways and propargylated with different propargyl bromides to give four mixtures of alkynyl allenes. The 4-alkylidene cyclopentenones were formed by a formal [2+2+1] cycloaddition of the alkynyl allenes using catalytic [Rh(CO)2Cl] 2 under CO atmosphere. Demixing by fluorous preparative HPLC, removal of the fluorous benzyl carbamates, and then exposure to HCl/ether gave the hydrochloride salts of 16 compounds as diastereomeric mixtures in 69-99\% purity. Thus, after just 26 chemical steps, a library of 16 cyclopentenones was prepared by using fluorous mixture synthesis. By comparison, the same library would have required 112 steps if each compound were made individually by parallel synthesis.}
}