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New sulfur-containing inorganic–organic hybrid polymers featuring B═N and B–O linkages are described. Sulfones, sulfoximines, and sulfoxides have been used as sulfur core units. An analogous sulfilimine proved unsuitable leading to an unprecedented side product. Aryl bromoboranes served as starting materials for the B═N and B–O linkages. For each polymer, the respective low-molecular-weight analogues were studied. Finally, degradation studies showed that the sulfur units can be regenerated by pH changes suggesting the new materials to be applicable in drug release programs.

At elevated temperatures, N-cyanosulfoximines react with Meldrum’s acid derivatives to give sulfoximines with N-bound 5-carbonyl-1,3-oxazine-2,4-dione groups. A representative product was characterized by single-crystal X-ray structure analysis. The product formation involves an unexpected molecular reorientation requiring several sequential bond-forming and -cleaving processes.