Triazabicyclodecene (1,5,7-triazabicyclo[4.4.0]dec-5-ene or TBD) is an organic compound consisting of a bicyclic guanidine. For a charge-neutral compound, it is a relatively strong base that is effective for a variety of organic transformations.  TBD is colorless solid that is soluble in a variety of solvents.