New extended anionic surfactants with a carboxylate or sulfate polar head were synthesized from polypropoxylated alcohols, and their structures were confirmed by 1 H and 13 C nuclear magnetic resonance analysis. The extended surfactant critical micelle concentration was found to decrease with the length of the polypropylene glycol spacer. Surfactants containing a diethylene glycol link to the head group exhibited a higher critical micelle concentration than did their nondiethoxylated homologs.

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A new class of extended surfactants was prepared in which the spacer arm between the polar portion and the hydrophobic alkyl chain was a polymer of propylene glycol with an average length of six propylene oxide units. The polar head was a single or double xylitol moiety or a xylitol molecule with carboxylic acid functionality. Surfactants containing double xylitol polar head groups showed a much higher critical micelle concentration value than surfactants with a single polar head.Paper no. S1456 in JSD 8, 193-198 (April 2005).

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The condensation of ω-unsaturated aldehydes with benzotriazole and secondary amines affords R-benzotriazolylalkenylamines that exist in solution as mixtures of the corresponding benzotriazol-1-yl and benzotriazol-2-yl isomers resulting from their rapid dissociation into iminium cations and the benzotriazolyl anion. The reduction of these adducts with samarium diiodide (SmI 2 ) takes place with formation of the benzotriazolyl anion and R-amino alkenyl radicals that undergo 5-or 6-exo-trig cyclizations leading to substituted cycloalkyl-or cycloheteroalkylamines. The presence of an electron-withdrawing substituent in the alkene subunit is required for efficient cyclizations. The formation of cyclopentylamines takes place with unusually high 1,5-cis selectivity (hex-5-enyl radical numbering), and the presence of a 2-or 4-Me substituent also imparts high 1,2-or 1,4-trans stereoinduction, respectively. The corresponding six-membered rings, however, are formed with low diastereoselectivity. Semiempirical calculations performed on model systems suggest that a stabilizing secondary orbital interaction between the amino group and the electron-deficient alkene might in part account for the enhanced cis-selectivity encountered. IntroductionSamarium diiodide (SmI 2 ) has emerged in the synthetic field as a versatile one-electron reducing agent capable of promoting a number of useful C-C bond-forming processes with high chemo-, regio-, and stereoselectivity. 1 SmI 2 -promoted couplings of carbonyl groups with alkyl-, acyl-, and aryl-halides, or with allylic-, propargylic-, and

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