New Reaction in the Ternary System Phenanthrenequinone–Phosphorus Trichloride–Arylacetylene

Abstract

It is known that the interaction of ortho -quinones with derivatives of trivalent phosphorus occurs rather readily and usually results in the formation of phosphoranes [1]. These derivatives of pentacoordinated phosphorus atom containing dioxaphospholene cycles are used in organic synthesis [2]. Recently, we showed that the reaction of phenanthrenequinone ( I ) with phosphorus trichloride and phenylacetylene as a third component under mild conditions ( 20°e ) yields a new heterocyclic system, 1,2-oxaphosphatriphenylene ( IIa ) [3]. Its content in the reaction mixture ranges up to 40–45%. Together with the formation of the phosphoryl group and the P–C bond, carbon is substituted for one of the oxygen atoms in phenanthrenequinone and chlorine is introduced selectively into the seventh position of the 1-oxa2-phosphatriphenylene heterocycle ( II ). The product of the interaction of quinone I with phosphorus trichloride, phosphorane III , which can be formed as an intermediate, is unstable and undergoes complex transformations in the absence of phenylacetylene.