A synthesis of 4,5-benzo-1-aza-tricyclo[4.3.1.1(3,8)]undecane (1), a benzo-1-aza-adamantane derivative, is described and features a previously unknown application of the Wolff-Kishner reduction of a nonresonance stabilized or "twisted" amide. An intermediate amino ester is converted to a severely "twisted amide", which, when exposed to hydrazine in alcohol, provides the corresponding "twisted" amino hydrazone. Wolff-Kishner conditions (KOH/ethylene glycol, 200 degrees C) provide the reduced target 1 without hydrolysis to amino acid derivatives. These operations are conveniently performed in a single flask in high yield.

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Noncoordinating solvents permit the halogen-metal exchange-induced formation of benzyne (aryne) from di- and trihalobenzene precursors in the presence of cyclopentadiene to give 1,4-dihydro-1,4-methano-naphthalenes. Studies with mixed halide precursors and nonacidic Diels-Alder diene traps reveal that ethereal and hydrocarbon solvents influence the halide leaving group facility, resulting in a reversal of 3-halobenzyne regioselectivity.

The key elimination step for the formation of 3-chloro- and 3-fluorobenzyne from 2-chloro-6-fluorophenyllithium displays a pronounced solvent-dependent regioselectivity. 6Li and 13C NMR spectroscopic studies on 2-chloro-6-fluorophenyllithium reveal a single monomeric aryllithium, suggested by DFT computational studies to be a trisolvate. Rate studies indicate that the elimination of LiCl and LiF proceeds via trisolvated and disolvated monomers, respectively.