Abstract Organolithium reagents prepared from BrC 6 H 4 SMR 3 compounds (R 3 M= Me 3 Si, Et 3 Si, PhMe 2 Si, Me 3 Ge) and butyllithium rearrange rapidly in ether solution to R 3 MC 6 H 4 SLi species, which upon treatment with water yield benzene thiols R 3 MC 6 H 4 SH. Under Wurtz—Fittig “in situ” conditions the organosodium intermediate NaC 6 H 4 SSiMe 3 does not rearrange but couples normally with Et 3 SiBr to give Et 3 SiC 6 H 4 ...