Search

A new family of macrocyclic ligands incorporating one or two fluorescent diaminobipyridine moieties is synthesized by the Buchwald—Hartwig amination reaction.

The Pd-catalyzed amination of isomeric dibromobiphenyls using linear oxadiamines, tri-, tetra- and pentaamines was carried out. 4,4’-Dibromobiphenyl provided a macrocycle comprising one biphenyl and one oxadiamine unit in tiny yield only with the longest diamine; on contrary, 3,3’-dibromobiphenyl gave target macrocycles in good yields, while 2,2’-dibromobiphenyl afforded only acyclic products.

Palladium-catalyzed amination of 1,2-dibromobenzene with equimolar amounts of linear polyamines leads to the formation of polyaza macrocycles in low yields. The use of 2-bromo-1,3-dichlorobenzene as starting compound ensures considerably larger yields of the target macrocycles, and the reaction is accompanied by side formation of N-aryl- and N,N′-diaryl-substituted polyamines, as well as of cyclic oligomers. The yields strongly depend on the polyamine chain length. Reactions of excess 2-bromo-1,3-dichlorobenzene with a series of polyamines gave the corresponding N,N′-diarylpolyamines in high yields, and the latter reacted with the second polyamine molecule to form cyclic dimers. A relation between the yield of cyclic dimers and polyamine structure was revealed.

Pd-catalyzed amination of a number of dihaloarenes with equimolar amounts of 1,3-bis(2-aminoethyl)adamantane in dilute dioxane solution provided one-step route to a new family of polyazamacrocycles with various cavity sizes containing one or several adamantane and aromatic fragments.

3,24-Bis(6-chloropyrdin-2-yloxy)cholane prepared from cholane-3,24-diol by the Mitsunobu reaction was successfully used to synthesize various polyaza macrocycles via palladium-catalyzed amination with linear polyamines. The contribution of side formation of cyclic oligomers was found to depend on the polyamine nature.

The synthesis of Nα,Nω-bis(haloaryl)polyamines and oxadiamines by Pd-catalyzed amination of 1,8-dichloroanthracene and 1,8-dichloroanthra-9,10-quinone is described, as well as the formation of 1,8-...

Reactions of alkynelsufenamides with olefins (such as cyclohexene, norbornene, 1-hexene, 1-octene, allylbenzene, and styrene) in the presence of phosphoryl halides (POCl3, POBr3) afforded 70–95% of β-halo-substituted alkyl alkynyl sulfides. The reactions with cyclohexene and norbornene are characterized by trans stereoselectivity. Alkynylsulfenylation of terminal alkyl- and benzylacetylenes occurs in a regioselective fashion with predominant formation of the corresponding anti-Markownikoff adducts, while the addition to styrene yields halogen-containing sulfides according to the Markownikoff rule.

Electrophilic sulfenylation of cyclic and open-chain conjugated dienes effected by a system arylsulfenamide-phosphorus oxyhalide was investigated. The initially formed adducts of 1,2-halosulfenylation in the course of the reaction and also at storage and chromatograqphic purification on silica gel undergo quantitative isomerization into a mixture of stereoisomeric products of 1,4-addition. The effect of halogen nature and the character of substituents in the benzene ring of arenesulfenamide on the addition rate of sulfenamides activated by phosphorus oxyhalides to open-chain and cyclic conjugated dienes and isomerization rate of the arising 1,2-adducts was examined.