Reaction of Me3SnLi with 1 equivalent of CuBrMe2S, PhSCu, Me2 (MeO) CC≍ C-Cu, or CuCN in tetrahydrofuran (THF) affords the (trimethylstannyl) copper (I) reagents Me3SnCuMe2S (1) and [Me3SnCuY] Li (Y= PhS (2), Me2 (MeO) CC≍ C (4), CN (5)), respectively. Similarly, treatment of a THF solution of Me3SnLi with 0.5 equivalent of CuBrMe2S provides (Me3Sn) 2CuLi (3), while reaction of n-Bu3SnLi with PhSCu (1 ...