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Introduction of fluorine atom(s) at the γ- and δ-positions of alkyl iodides increased the selectivities toward palladium-catalyzed cross-coupling reaction with organostannanes. A similar effect of fluorine substituents on the selectivities was also observed in the palladium-catalyzed carbonylative coupling reaction of alkyl iodides with phenyltributyltin under CO pressure.

β-Perfluoroalkyl-substituted alkyl halides reacted with organostamnanes such as allylphenylethynyl-, β-phenylethenyl-, and phenyl-tributyltin in the presence of palladium-phosphine complexes to give the corresponding cross-coupling products in good yields. When the reaction was carried out under CO pressure, carbonylative coupling of the halides took place affording the corresponding fluorine-contaming ketones in good yields.

Coupling reaction of β-perfluoroalkyl-substituted alkyl halides with Grignard reagents such as phenyl-, vinyl-, allyl-, benzyl-, and alkyl-magnesium halides was catalyzed by copper salts or complexes to give the corresponding cross-coupling products in good yields. α,ω-Diiodoalkane bearing a polyfluoroalkylene moiety also reacted with 2 equiv. of Grignard reagent in the presence of copper catalyst to give α,ω-bi-functionalized product.

1,2,3,4-Tetra-t-butylnaphthalene (2), a highly crowded naphthalene derivative, has been synthesized. Upon irradiation, 2 underwent photovalence isomerization to afford 1,2,5,6-tetra-t-butyl-3,4-benzo-3-tricyclo[3.1.0.02,6]-hexene (3). The synthesis of 1,4,5,6-tetra-t-butyl-2,3-benzo-2,5-bicyclo[2.2.0]hexadiene (1), which was used for the synthesis of 2, is also described.