The reaction of l,l,l,3,3,3-hexafluoro-2-phenyl-2-propanol (RFOH) with either sec-butyllithium or n-butyllithium/IVJVrZV' JV'-tetramethylethylenediamine (TMEDA) provides 3, a reagent for the facile introduction of a bidentate ligand which is particularly effective in stabilizing the higher coordination states of nonmetallic elements. This reagent is used to prepare a series of spiro compounds in which two of these ligands are attached to hypervalent silicon (anionic lO-Si-5 species 6a-d, 13), phosphorus (10-P-5 phosphoranoxide salt 8), sulfur (the very unreactive sulfurane, 10-S-4 species 9), or iodine (10-1-3 species 15). Reaction of 3 with SiCL, gives the expected spirosilane, 12, an 8-SÍ-4 species which reacts with a variety of nucleophiles to give pentacoordinate silicon (lO-Si-5) species. For example, reaction of 12 with phenyllithium gives 6a. The much weaker nucleophile 4-(dimethylamino)pyridine gives a stable complex which involves nitrogen attack at silicon. Reaction of 3 with elemental sulfur gives disulfide diol 7a. Reaction with either 1,2-dibromoethane or elemental bromine gives bromo alcohol 11a, while I2 reacts with 3 to give iodo alcohol lib.

Polysaccharide-based tissue adhesives are efficacious in sealing corneal wounds and are non-cytotoxic to corneal endothelial cells. Such adhesives represent a promising new technology for ophthalmic surgery.

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Aqueous dispersions (0.1 wt %) of hydrogels 1 and 5-formed by crosslinking polyallylamine hydrochloride (MW 60,000) with aldaric acid derivatives, diethyl L-tartrate and N,N 0 -bis(methoxycarbonylmethyl)-D-glucaramide, respectively-exhibited complete (log 5) kill within 4 h of Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans suspended in culture medium. This antimicrobial activity was much higher than that of uncrosslinked polyallylamine (1 wt % killed only 75% of E. coli in 24 h). When dispersed at 10 and 100 ppm, hydrogel 5 displayed complete (log 5) kill of E. coli within 30-60 and 15 min, respectively. Hydrogels 1 and 5 were active against S. aureus and Salmonella choleraesuis dried on hard stainless steel surfaces and accelerated the deaths of E. coli, P. aeruginosa, S. aureus, and C. albicans in a model skin cream formulation. A 0.8% aqueous dispersion of hydrogel 5 was also effective as a hand sanitizer, killing 99.7% of Serratia marcescens on human hands within 5 min. Hydrogels 1 and 5 caused no dermal irritation or allergic contact sensitization under the conditions of a human repeat insult patch test.