%0 Journal Article
%T Synthesis of Polycyclic Ring Systems Using Transition Metal Catalyzed Cyclizations of Diazo Alkynyl Ketones
%A Albert Padwa
%J Molecules
%D 2001
%I MDPI AG
%R 10.3390/60100001
%X The rhodium(II)-catalyzed reaction of ¦Á-diazo ketones bearing tethered alkyne units represents a new and useful method for the construction of a variety of substituted cyclopentenones. The process proceeds by addition of the rhodium-stabilized carbenoid onto the acetylenic ¦Ð-bond to give a vinyl carbenoid intermediate. The resulting rhodium complex undergoes a wide assortment of reactions including cyclopropanation, 1,2-hydrogen migration, CH-insertion, addition to tethered alkynes and ylide formation. When 2-alkynyl-2-diazo-3-oxobutanoates were treated with a Rh(II)-catalyst, furo[3,4-c]furans were formed in excellent yield.
%K rhodium
%K catalyst
%K diazo
%K ketone
%K alkyne
%K cyclization
%K CH-insertion
%K ylide
%K furo[3
%K 4-c]furans
%U http://www.mdpi.com/1420-3049/6/1/1