Transition metal complexes enediynes

Nitrogen-containing 15-membered trialkyne macrocycles, such as l,6,ll-frw(aiylsulfonyl)-l,6,ll-triazacyclopentadeca-3,8,13-triynes and enediynes as 1,6,11-frw(arylsulfonyl)-1,6,11-triazacyclopentadeca-3-ene-8,13-diynes have been prepared and subjected to a [2+2+2]-cyclotrimerization process catalyzed by transition metal complexes, e.g., RhCl(CO)(PPh3)2 <05JOC2033>. The reaction of pemosylated diethylenetriamine and 2-substituted propan-1,3-... 

The transition metal catalyzed cycloaddition-carbocyclization reaction is an effective technique for the formation of complex polycyclic systems [4]. Various versions of these reactions are described below, including [2+2+2+1] [154], [4+2+2] [155], [5+1+2+1] [156], [3+3+1] [157] and [5+2+1] [158] cycloaddition. These reactions are often used for the synthesis of complex molecules and natural products [158]. On the other hand, the discovery of natural 5-7-6-S tetracyclic condensed system, such as Caribenol A [159], contribute to the development of highly efficient synthetic methods for the creation of polycyclic cores in one step starting with the enediynes [160]. 

---