Semi-Rigid Bis-Phosphane Ligands for Metallamacrocycle Formation

Abstract

Efficient syntheses are described for the new bridging bisphosphanes DPPN (4) and DPEN (5) built around the restricted rigidity of a 2,7-dialkoxynaphthalene backbone. These show marked preference for bridging pairs of metal atoms (Pt II , Mo 0 ) to form metallamacrocycles or oligomers. Single-crystal X-ray structure determinations of four dimeric

Discovery of anion–π interactions in the recognition mechanism of inorganic anions by 1,2,3-triazolium rings

“…The novel bidentate triazolium receptor 1 2+ Á2BF 4 À was prepared from 2,7-bis(2-azidoethoxy)naphthalene, available in 86% yield from sodium azide and 2,7-bis(2-hydroxyethoxy)naphthalene bis(methanesulfonate)ester, 24 by a copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) 25 Stepwise addition of the above-mentioned set of anions to a solution of the receptor 1 2+ Á2BF 4…”

One-pot synthesis of cyclophane-type macrocycles using manganese(iii)-mediated oxidative radical cyclization

“…Reaction of alkadienes 1 with bis(3-oxobutanoate)s 2 containing aromatics in the presence of manganese(III) acetate 1,9-Octadiene 1 (6) was prepared by the Grignard reaction of diethyl octanedioate with phenylmagnesium bromide followed by dehydration. Bis(3-oxobutanoate) containing aromatics, 2 (1) -para, was synthesized by the reaction of hydroquinone with bromoacetate under basic conditions, followed by reduction with lithium aluminium hydride 14 and then esterification with a diketene. 13 With the diene 1 (6) and the bis(3-oxobutanoate) 2 (1) -para in hand, we examined the reaction of 1 (6) with 2 (1) -para in the presence of manganese(III) acetate.…”

“…Other bis(3oxobutanoate)s containing aromatics 2 (n) -arom (n = 1,2,3) were also prepared by the Williamson ether synthesis of the corresponding phenolic diols with (chloroethoxy)ethanols followed by esterification with a diketene. 14 When the reaction of the dienes 1 (m) and 1 (O) with bis(3-oxobutanoate)s 2 (n) -arom was carried out under the optimized reaction conditions (Scheme 2), the desired cyclic compounds, 3 (m)(n) -arom and 3 (O)(n) -arom, were produced in the yields shown in Table 2.…”

“…4-oxa-1,6-heptadiene 1 (O) was prepared by the Reformatsky reaction of benzophenone with ethyl a-bromoacetate followed by reduction with lithium aluminium hydride and then dehydration. 14,23 Oxamethylene bis(3-oxobutanoate)s containing aromatics 2 (n) -arom (n = 1,2,3) and p-phenylene bis(allyoxy)ethyl ethers 4 (m) (m = 1,2,3) were prepared by the Williamson ether synthesis of the corresponding aromatic diols with (chloroethoxy)ethanols, followed by esterification with the diketene or the reaction of 3-bromo-1,1-diphenylpropene under basic conditions. 10a,14 p-phenylenebis(7,7-diphenyl-6-heptene) (6) and p-phenylenebis(heptyl) bis(3-oxobutanoate) (8) were synthesized by the modified method described in literature.…”

Intermolecular Addition Reactions onto CC Multiple Bonds

“…The photochemical reaction of bisallyloxynaphthalene with diphenylphosphane gave, smoothly, a bridged bisphosphane (70% yield) that was used to form metallamacrocycles or oligomers with Pt(II) or Mo(0) [43]. Olefins containing a tris-ethoxysilyl functionality have been also widely used for photoinduced CÀP bond formation.…”