This review summarizes our recent results on the synthesis of various 6-, 7- and 8-membered ring phosphorus heterocycles. The key intermediates are the 3-phosphabicyclo[3.1.0]hexane 3-oxides obtained from dihydro-1H-phosphole 1-oxides by dichlorocarbene addition. The opening of the dichlorocyclopropane ring in these intermediates may afford dihydro- or tetrahydrophosphinine oxides, while the Friedel-Crafts reaction of the adducts gives benzo-phosphabicyclooctenes. The dihydrophosphinine oxides were further utilized in the preparation of hexahydrophosphinine oxides, phosphinines, 1,4-dihydrophosphinine oxides, phosphepine oxides and phosphabicyclooctadienes.