Two new copper(I) arenethiolates with ortho-chelating nitrogen donor atoms [Cu(SC(6)H(4)NMe(2)-2)](3) (5) and [Cu(S-1-C(10)H(6)NMe(2)-8)](9) (6) have been synthesized by reacting Me(3)SiSAr (Ar = C(6)H(4)NMe(2)-2 or 1-C(10)H(6)NMe(2)-8) with copper(I) chloride in a 1:1 molar ratio. Copper(I) arenethiolate 5 is a white to pale yellow solid and is trimeric in the solid state as well as in solution. Crystals of [Cu(SC(6)H(4)NMe(2)-2)](3) (5), C24H30Cu3N3S3, are trigonal, space group R3, with a = b = 18.2325(7) Angstrom, c = 6.8410(4) Angstrom, V = 1969.4(2) Angstrom(3), Z = 3, and final R = 0.028 for 1010 reflections with I greater than or equal to 2.5 sigma(I) and 107 variables. Copper(I) arenethiolate 6 forms dark red crystals and is nonameric in the solid state as well as in solution.Crystals of {[Cu(S-1-C(10)H(6)NMe(2)-8)](9)}(2){C6H6}(10.5) (6), C279H279-Cu18N18S18, are triclinic, space group , with a = 16.081(2) Angstrom, b = 26.650(4) Angstrom, c = 32.747(6) Angstrom, alpha = 67.320(13)degrees, beta = 76.180(12)degrees, gamma = 81.226(12)degrees, V = 12545(4) Angstrom(3), Z = 2, and final R = 0.118 for 28749 reflections and 1501 variables. Reaction of nonameric 6 with (3,3-dimethylbutynyl)copper results in he formation of the 2:1 mixed dimeric hexanuclear organo(arenethiolato)copper aggregate [Cu-3(S-1-C(10)H(6)NMe(2)-8)(2)(C=CBu)](2) (9), C60H66Cu6N4S4, which has been isolated as an air-stable orange solid which is insoluble in most common organic solvents. Crystals of 9 are monoclinic, space group P2(1)/c, with a = 11.9839(5) Angstrom, b = 12.9391(8) Angstrom, c = 18.9482(7) Angstrom, beta = 108.326(3)degrees, V = 2789.1(2) Angstrom(3), Z = 2, and final R = 0.0314 for 5110 reflections with I greater than or equal to 2.5 sigma(I) and 358 variables. Reaction of 6 with mesitylcopper, [Cu-5(C(6)H(2)Me(3)-2,4,6)(5)], results in the formation of the 1:1 mixed organo(arenethiolato)copper aggregate [Cu-2(S-1-C(10)H(6)NMe(2)-8)(C(6)H(2)Me(3)-2,4,6)](n), (10), which is a yellowish-brown, slightly air-sensitive solid that is soluble in polar and aromatic hydrocarbons. The new mixed aggregates 9 and 10 are thermodynamically and kinetically very stable, and it is found that the overall structure of mixed organo(arenethiolato)copper aggregates such as 9 is insensitive to structural changes in the arenethiolate ligand.