The reaction between [Mo(NO)(Tp*)I-2] {Tp(*-) = hydrotris(3,5-dimethylpyrazol-1-yl)borate) and 2,7-dihydroxynaphthalene affords, as its major product, the binuclear complex [Mo(NO)(Tp*)(2,7-O2C10H6)](2) The reaction appears to proceed under kinetic control so that shorter reaction times afford the syn-isomer (47% yield after 40 min) while longer reaction times allow the and-isomer (43% yield after 48 h) to be obtained. The molecular structures of anti-[Mo(NO)(HB(3,5-Me2C3HN2)(3))} 2,7-O2C10H6)](2).2CHCl(3).CH2Cl2 (1), syn-[Mo(NO){HB(3,5-Me2C3HN2)(3))(2,7-O2C10H6)](2). Me2C3HN2)(3)}(2,7-O2C10H6)](2).0.67CHCl(3).2.7H(2)O (2) and syn-[MoNO)(HB(3,5-Me2C3HN2)(3)}(2,7 CO (3) have been determined crystallographically (1) C50H56B2N14O6Mo2.2CHCl(3).CH2Cl2, triclinic, space group P (1) over bar, a = 11.535 (2) Angstrom, b = 14.032(3) Angstrom, c = 11.247(3) Angstrom, alpha = 94.70(1)degrees, beta = 102.30(2)degrees, gamma = 110.31(2)degrees, Z = 1; (2) C50H56B2N14O6Mo2.0.67CHCl(3).2.7H(2)O, monoclinic space group P2(1)/m, a = 23.770(7) Angstrom, b = 26.600(10) Angstrom, c = 11.224(4) Angstrom, beta = 99.86(2)degrees, Z = 4; (3) C50H56B2N14O6Mo2.3C(3)H(6)O, triclinic, space group P (1) over bar, a = 16.929(3) Angstrom b = 17.465 Angstrom, c = 12.739(2) Angstrom, alpha = 100;06(1)degrees, beta = 94.93(2)degrees, gamma = 114.13(1)degrees, Z = 2. In 1 each nitric oxide ligand is hydrogen bonded [C-H 0.98, H ... O 2.26, C ... O 3.13(2) Angstrom, C-H ... 147 degrees} to a chloroform molecule which lies within a cavity in the moleculr having as its base a bridging 2,7-naphthalenediyl fragment and as its sides a part of each HB(3,5-Me2C3HN2)(3) ligand. No hydrogen bonding interactions with nitric oxide are apparent in the strucutres of 2 and 3.