Fused tetracycles with a benzene or cyclohexadiene core: [2 + 2 + 2] cycloadditions on macrocyclic systems.
نویسندگان
چکیده
A series of fused tetracycles with a benzene or cyclohexadiene core (2a-h) is satisfactorily prepared by intramolecular [2 + 2 + 2] cycloadditions of triynic and enediynic macrocycles (1a-h) under RhCl(PPh3)3 catalysis; the enantioselective cycloaddition of macrocycles 1b and 1e and gives chiral tetracycles with moderate enantiomeric excess.
منابع مشابه
Fused tetracycles with a benzene or cyclohexadiene core: [2 + 2 + 2] cycloadditions on macrocyclic systemsw
The transition-metal-catalyzed [2 + 2 + 2] cycloaddition of alkynes is an interesting method for synthesizing polysubstituted benzene derivatives. When running this reaction intramolecularly, three fused rings are formed in one synthetic operation. Furthermore, when it is performed in a closed system, i.e. a macrocycle, the reaction leads to fused tetracycles, which is a highly attractive synth...
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ورودعنوان ژورنال:
- Chemical communications
دوره 36 شماره
صفحات -
تاریخ انتشار 2008