Synthesis of Phosporus Heterocycles using the Donor-Stabilized Dithiomonometaphosphoryl Chloride as Preparative Tool

Abstract

The reactivity of the donor-stabilized monometaphosphoryl chloride Py⇒PS₂Cl (1) versus multiple bond systems and organometallic compounds has been studied. Thus, on the reaction of 1 with diphenyl acetylene at elevated temperature the five-membered ring systems 2–4 are formed. In the first step probably cycloaddition of the intermediary liberated free monometaphosphoryl chloride PS₂Cl with diphenyl acetylene leads to the 1-thia-phosphacyclobut-3-ene 6. This assumption will be supported by theoretical calculations. Attempts to eliminate one sulfur atom from the disulfide bridge in 2 result in the bicyclic ring system 5 besides a compound which is assumed to be 6. The reaction of 1 with tertBuLi gives the dithiaphosphetane 7 whereas with NaN(SiMe₃)₂ the diazadiphosphetidine 8 is obtained.

Keywords::

• Phosphorus heterocycles
• dithiomonometaphosphoryl chloride
• cycloaddition reactions