Effective, one-pot syntheses of 2,3-disubstituted furans and thiophenes, exploiting 2-tert-butyldimethylsilyl-3-formylfuran and -thiophene as the respective bifunctional linchpins, have been developed. The synthetic protocol involves multicomponent type II Anion Relay Chemistry (ARC) mediated by a solvent-controlled C(sp(2))-->O 1,4-Brook rearrangement. Simple organolithiums and alpha-disubstituted ester enolates prove effective as the initiating nucleophiles.