Bis heterocycle-N-yl alkanes

Condensation of benzaldehydes with benzotriazole in the presence of thionyl chloride readily gives a,a-/fe(benzo-triazol-l-yl)toluenes 727 that can be considered as l,l -gm-dicarbanion equivalents. Thus, treatment of derivatives 727 with ketones and lithium metal suspended in THF at — 78 °C generates substituted propylene glycols 728 (Equation 18) 1998TL2289 . 

R2R3C=0=cyclopentanone, cyclohexanone, 2-pentanone, 3-pentanone, or 4-heptanone 

Ar = 4-Me-C6H4, 4-MeO-C6H4, 4-CI-C6H4, 2-furyl, 2-thienyl, or PhCH=CMe 

Compounds of general structure 745 (and their benzotriazol-2-yl analogs) are discussed in this subsection. 

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