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The synthesis of branched partially fluorinated nonionic Y-shaped surfactants, with the general formula C F nC2N(EmM)2, where C F n denotes fluorinated alkyl chain F(CF2)n with n ) 4-10, C2 is C2H2, and EmM is oligooxyethylene monomethyl ether with m ) 2, 3, and their hydrocarbon analogs Cn+2N(EmM)2 (Cn equals hydrocarbon chain) is described. These surfactants are synthesized to analyze the influence of the fluorinated alkyl chain on the packing effects to amphiphilic layers in a binary surfactant/water system. The lyotropic phase behavior of these surfactants is investigated by polarizing microscopy. The liquid crystalline (LC) phase polymorphism of the fluorinated C F nC2N(E3M)2 surfactants strongly changes with n from hexagonal H1 phase (n ) 6) to lamellar LR phase (n ) 10). In contrast to other Y-shaped hydrocarbon oligooxyethylene surfactants CnG(EmM)2 (where G denotes a glycerol unit) which form only cubic I1 and H1 phases for n ) 12-16 and m ) 3-5, the phase behavior of the C F nC2N(EmM)2 surfactant/water systems shows a remarkable change in the LC phase polymorphism (from H1 to LR phase) with n and m. Compared to hydrocarbon surfactants these results distinctly confirm the influence of more rigid fluorinated alkyl chain on the phase behavior.

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The complete assignment of the proton and carbon NMR spectra for seven sequiterpene alcohols isolated from the heartwood oil of Neocallitropsis pancheri, namely, a-, p -and y-eudesmol. carissone, guaiol, bulnesol and elemol, w a s achieved * For Part 7. see Ref. 3 using the concerted application of oneand two-dimensional NMR techniques including DEPT, COSY, HETCOR and H MBC spectroscopy. The parameters previously reported in the literature were found t o be often wrong or incomplete.