Preparation of organometallic uracil-analogue Fischer carbene complexes: Comparative study of conventional heating vs microwave irradiation

Mono and disubstituted ureas react with alkynyl Fischer carbene complexes to give mono and di N,N-substituted organometallic uracil analogues. An optimization of the process using different starting metal carbene complexes and variously substituted ureas under conventional heating (with and without solvent) and microwave irradiation techniques is reported. The synthesis of the metal–carbene analog of the commercially available dimethyl uracil is reported.

Graphical abstractOrganometallic uracil-analogues of Fischer carbene complexes are readily accessible through reaction of alkynyl alkoxy carbene metal complexes with mono and dimethylureas. The synthetic utility of this methodology was demonstrated by the preparation of a variety of Fischer carbene complexes incorporating the uracil skeleton, and applied to the synthesis of the organometallic analog of the commercial dimethyl uracil.Figure optionsDownload full-size imageDownload as PowerPoint slide