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Reactivity and stability of trifluoromethylcyclohexane (TFMC) has been investigated towards various reagents, in order to evaluate its possible use as solvent. TFMC is stable in most oxidizing conditions, indicating the protective effect of a fluoroalkyl substituent towards oxidation, and surprisingly, it is also very stable towards strong bases. TFMC has also been assessed as a chlorinated solvent substitute in some reactions. It is clearly adapted as a CCl 4 substitute in allylic bromination reaction.

The chiral titanium complex-catalyzed ene-type reaction and the Mukaiyama aldol reaction with fluoral are shown to serve as an efficient route to the enantioselective and diastercoselective synthesis of CF 3 -substituted components of biological and synthetic importance.

The chiral titanium complex-catalyzed carbonyl-ene reaction with fluoral is shown to serve as an efficient route for the syn-diastereoselective and enantioselective synthesis of CF3-substituted compounds of biological and synthetic importance.

The chiral titanium complex-catalyzed carbonyl-ene reaction with fluoral is shown to serve as an efficient route for the syn-diastereoselective and enantioselective synthesis of CF3-substituted compounds of biological and synthetic importance.

The chiral titanium complex-catalyzed ene-type reaction and the Mukaiyama aldol reaction with fluoral are shown to serve as an efficient route to the enantioselective and diastercoselective synthesis of CF 3 -substituted components of biological and synthetic importance.

4-Fluoro-2-( F -ethyl)-3-( F -methyl)-1, 5-benzoxazepine was prepared by reaction of F -2-methyl-2-pentene with 2-aminophenol in the presence of triethylamine in diethyl ether. The reaction of F -2,4-dimethyl-3-heptene with 2-aminophenol in dimethylformamide gave 7-( F -1-methylethyl)-8- ( F -ethyl)-9,14-benzoxazepino[4,3-b]1,6-benzoxazepine. Several ortho-bifunctional benzenes reacted similarly with F -2-methyl-2-pentene and F -2,4-dimethyl-3-heptene to give the corresponding seven-membered benzoheterocycles.

The treatment of dialkyl bromodifluoromethylphosphonates with activated zinc dust in various solvents gave dialkoxyphosphinyldifluoromethy1zinc compounds 2, which were acylated with acid halides or fluorinated acid anhydride to afford dialkyl 2-oxo-1,1-difluoroalkylphosphonates in good yields.

Reactions of perfluoro-2- and -4-methyl-2-pentenes with thiols were found to involve an oxidation-reduction system. 1,4-Elimination of sulfenyl fluorides from thio-substituted perfluoroolefins forming 1,3-dienes and disulfides is suggested as the reaction pathway.

Reactions of F -2- and -4-methly-2-pentenes with thiols were found to involve an oxidation-reduction system. 1,4-Elimination of sulfenyl fluorides from thio-substituted perfluoroolefins to form 1,3-dienes and disulfides is suggested as the reaction pathway.

A room temperature method for the conversion of perfluoroalkyl iodides to α-perfluoroalkyl carbinols under Pd or Ni catalysis is reported. The use of trifluoromethyl bromide provides an economical procedure for trifluoromethyl substituted carbinols.

Nucleophilic substitution on F -2,4-dimethyl-3-heptene (3) by sodium phenoxide in diethyl ether gave 3-phenoxylated F -2,4-dimethyl-4- (5) and -3-heptenes (6). In contrast, the reaction of (3) with phenol and triethylamine in dimethylformamide afforded 4-phenoxylated F -2,4-dimethyl-3-heptene (7) as the major product. The reaction mechanisms are discussed.

Nucleophilic reactions of F-2-methyl-2-pentene (1) and (E)-F-4-methyl-2-pentene (2), the dinners of hexafluoropropene, with organomagnesium and -lithium reagents were investigated. The reaction of 1 proceeded readily, giving two alkyl- or aryl-substituted polyfluoroalkenes which resulted from α- and γ-fluorine elimination, respectively. Only phenyllithium reacted with 2, giving also α- and γ-fluorine eliminated phenylpolyfluoroalkenes. The reaction mechanism of γ-elimination was postulated in relation to the electropositive property of the organo group and to Mg–F or Li–F bond formation.

A room temperature method for the conversion of perfluoroalkyl iodides to α-perfluoroalkyl carbinols under Pd or Ni catalysis is reported. The use of trifluoromethyl bromide provides an economical procedure for trifluoromethyl substituted carbinols.

Reactions of perfluoro-2- and -4-methyl-2-pentenes with thiols were found to involve an oxidation-reduction system. 1,4-Elimination of sulfenyl fluorides from thio-substituted perfluoroolefins forming 1,3-dienes and disulfides is suggested as the reaction pathway.

Nucleophilic reactions of F-2-methyl-2-pentene (1) and (E)-F-4-methyl-2-pentene (2), the dinners of hexafluoropropene, with organomagnesium and -lithium reagents were investigated. The reaction of 1 proceeded readily, giving two alkyl- or aryl-substituted polyfluoroalkenes which resulted from α- and γ-fluorine elimination, respectively. Only phenyllithium reacted with 2, giving also α- and γ-fluorine eliminated phenylpolyfluoroalkenes. The reaction mechanism of γ-elimination was postulated in relation to the electropositive property of the organo group and to Mg–F or Li–F bond formation.

The treatment of dialkyl bromodifluoromethylphosphonates with activated zinc dust in various solvents gave dialkoxyphosphinyldifluoromethy1zinc compounds 2, which were acylated with acid halides or fluorinated acid anhydride to afford dialkyl 2-oxo-1,1-difluoroalkylphosphonates in good yields.

The title phosphonates are readily prepared in excellent yield via the Michaelis- Arbuzov reaction of trialkylphosphites and dibromo- F -methane. These bromo- F -methyl phosphonates are metallated directly with either cadmium or zinc powder in various solvents to give high yields of stable organometallics. These metallated intermediates serve as a synthetically useful source for the introduction of the difluoromethyl phosphonate group into organic molecules. Wittig olefination gives F -methylene olefins and acylation produces β -ketophosphonates, which are readily cleaved with fluoride ion and serve as a convenient entry to fluoro enolates. The preparation of the titled phosphonates and their synthetic utility will be presented.