TMPMgCl·LiCl and TMPZnCl·LiCl allow facile magnesiation and zincation, respectively, of the 1,4-dithiin scaffold, producing polyfunctionalized 1,4-dithiins. A subsequent metalation of these S-heterocycles can also be achieved with the same TMP bases, leading to 2,3-disubstituted-1,4-dithiins. The Mg- and Zn-TMP bases allow as well the successful metalation of 1,4,5,8-tetrathianaphthalene and 1,4,5,6,9,10-hexathiaanthracene.

The reaction of mixtures of aryllithium regioisomers obtained either by directed lithiation or by Br/Li exchange with substoichiometric amounts of Cp 2 ZrCl 2 proceeds with high regioselectivity.T he least sterically hindered regioisomeric aryllithium is selectively transmetalated to the corresponding arylzirconium species leaving the more hindered aryllithium ready for various reactions with electrophiles.A sa na pplication, these regioselective transmetalations from Li to Zr were used to prepare all three lithiated regioisomers of 1,3-bis(trifluoromethyl)benzene.

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Polyfunctional silylated cyanohydrins are readily magnesiated or zincated with TMPMgCl·LiCl or TMP2Zn·2MgCl2·2LiCl leading to the corresponding metallated derivatives. These Mg- or Zn-derivatives react with various electrophiles such as benzylic bromides, allylic bromides, acid chlorides, aldehydes, NCCO2Et, or MeSO2SMe. Subsequently, TBAF-deprotection provides the corresponding keto or 1,2-diketo derivatives.

Lithiation of a variety of substituted arenes gives regioisomeric mixtures of aryllithium intermediates.Transmetalation with a substoichiometric amount of ZrCl2Cp2 transmetalates the least sterically hindered aryllithium intermediate, leaving the more hindered regioisomers for reactions with a variety of electrophiles.