The 1:1 reactions with (R(3)P)(2)MCl(2) (M = Ni, Pd, and Pt) have been surveyed, and bicyclic cage compounds containing boron, phosphorus and transition metal (Ni, Pd, or Pt) atoms have been isolated and characterized. The molecular structures of the species (Et(3)P)(2)Pd(PBN(i)Pr(2))(2) (2), (Et(3)P)(2)Pd(PBtmp)(2) (3), and (Et(3)P)(2)Pt(PBN(i)Pr(2))(2) (4) have been determined by single-crystal X-ray diffraction techniques. 2 crystallized in the monoclinic space group C2/c with a = 20.212(4) Å, b = 10.225(1) Å, c = 17.460(2) Å, beta = 107.72(1) degrees, and Z = 4. 3 crystallized in the orthorhombic space group P2(1)2(1)2(1) with a = 12.606(1) Å, b = 12.618(1) Å, c = 24.221(3) Å, and Z = 4. 4 crystallized in the monoclinic space group C2/c with a = 20.195(3) Å, b = 10.187(2) Å, c = 17.280(2) Å, beta = 107.53(7) degrees, and Z = 4. The spectroscopic and structural features of the new cage compounds are discussed in relation to their main group element cage analogs.