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Lithium amides have been extensively studied [170] and the potential of metal amides in synthesis is well understood [171]. However, the susceptibility of many DMGs to nucleophilic attack, even in the presence of amides [172, 173], has meant that sterically demanding reagents have necessarily come to the fore. Indeed, sterically cumbersome LTMP has been used for the directed ortho‐lithiation of arylcarboxylic esters. However, unwanted condensation between the aryllithium intermediate and electrophilic directing groups has still been known to occur during metalation [12]. These formative ideas were, however, used in attempts to develop new chemoselective metalating agents capable of the deprotonative reaction – zincation in the first instance – of functionalized aromatics and heteroaromatics. The early research in this area led to TMP‐zincate reagents being developed as outlined below [174, 175].