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Methods have been developed for functionalizing the alkaloid cytisine via introduction of alka-1,3- and -2,3-dien-2-ylphosphonate fragments. The main pathway of the reaction of cytisine with 2-(diethoxyphosphoryl) alka-2,3-dien-1-yl methanesulfonates is nucleophilic substitution of the methanesulfonyloxy group with retention of the alkadiene skeleton. A minor reaction pathway is nucleophilic substitution with formation of alka-1,3-dien-2-ylphosphonates. Cytisine conjugates with exclusively alka-1,3-dien-2-ylphosphonate fragment have been synthesized by copper(I)-catalyzed 1,3-dipolar cycloaddition of N-(prop-2-yn-1-yl)cytisine to 3-azidoalka-1,3-dien-2-ylphosphonates.

Cytisine and anabasine derivatives containing an acetylenic fragment were used as building blocks in 1,3-dipolar cycloaddition reactions with substituted N-hydroxybenzenecarboximidoyl chlorides, catalyzed by copper(I) salt. The reactions with N-propargylcytisine were not selective, and the products were mixtures of 3,5-disubstituted isoxazoles and small amounts (5–8%) of 3,4-disubstituted isomers. 1,3-Dipolar cycloaddition with N-propargylanabasine afforded 3,5-disubstituted isoxazole derivatives with high regioselectivity.

Diethyl phosphonate rapidly reacted with hexamethyldisilazane at 20°C in the presence of 52 mol % of zinc(II) chloride to give 76% of diethyl trimethylsilyl phosphite.

Simple procedures have been developed for the synthesis of 2-chloro-5,5-dimethyl-2,5-dihydro- 1,2λ5-oxaphosphole 2-oxide by one-pot electrophilic cyclization of 3-methylbuta-1,2-dien-1-ylphosphonic dichloride and of (Z)-4-[dialkyl(diphenyl)phosphoryl]-2-methylbut-3-en-1-ol by reaction of 2-chloro-5,5-dimethyl- 2,5-dihydro-1,2λ5-oxaphosphole 2-oxide with organomagnesium compounds.

Reactions of [fluoro(methylsulfonyloxy)iodo]benzene with norbornene, cis-5-norbornene-endo-2,3-dicarboxylic acid, and cis-5-norbornene-endo-2,3-dicarboxylic anhydride were studied. A new mild procedure was developed for introduction of fluoro and sulfonyloxy or two sulfonyloxy groups into molecules of norbornene and its derivatives.

Reactions of [fluoro(sulfonyloxy)iodo]benzene with 1-hexene and 1-heptene smoothly yield the corresponding 1,2-disulfonates. Reaction of [fluoro(sulfonyloxy)iodo]benzenes with methyl methacrylate results in formation of isomeric α-fluoro-β-sulfonyloxy products. A possible reaction mechanism is discussed.