Synthesis and characterization of new metallo and metal-free porphyrazines containing dioxadithia (O2S2) and tetrathia (S4) macrocyclic moieties

Abstract

Abstract The synthesis of new magnesium porphyrazines, peripherally substituted with 14-membered dioxa-dithia (O 2 S 2 ) and tetrathia (S 4 ) macrocycles has been accomplished by cyclotetramerization of (6Z)-1,3,4,9,10,12-hexahydro-2,5,8,11-benzodioxadithia-cyclotetradecine-6,7-dicarbonitrile ( 3 ) or (6Z)-1,3,4,9,10,12-hexahydro-2,5,8,11-benzotetrathiacyclotetradecine-6,7-dicarbonitrile ( 5 ) in the presence of magnesium butanolate. The precursors were prepared from disodium salt of dithiomaleonitrile and o -xylenebis(1-chloro-3-oxapentane) ( 2 ) or o -xylenebis(1-chloro-3-thiapentane) ( 4 ). The metal-free porphyrazines are obtained by the treatment of these magnesium porphyrazines with trifluoroacetic acid. These new compounds are characterized by a combination of elemental analysis and 1 H, 13 C NMR, IR, UV–vis and MS spectral data.