(A=B) + (X-Y) => X-A-B-Y

AR-SO₂-Cl + RNH₂ => AR-SO₂-NHR

AR-H + ClSO₃H => Ar-SO₂Cl

RX + R'H => R-R'

R-COOH + R'OH => R-COO-R'

R-COO-R' + R"OH => R-COO-R" + R'OH

R-X + R'OH => R-O-R'

RCOOH => RCOONa

HX + RNH₂ => RNH₂-HX

R₁R₂R₃N + RX => RR₁R₂R₃N+X-

AX + Y => AY + X

R-OH + ClSO₃H => R-OSO₃-H

AR-H + SO₃ => AR-SO₃H