Planar-Chiral Macrobicycles Comprising Cyclam Moiety

Abstract

Macrobicycles derived from 1,8-disubstituted cyclam in principle may be planar-chiral provided that the second chain cannot rotate around the cyclam fragment. Hindered rotation is enabled by the introduction of two additional substituents at nitrogen atoms and by enough short chain which forms the second cycle. N,N',N",N'"-tetrasubstituted cam.ac.uk), deposit number CCDC 912600. Benzyl bromide, 3-bromobenzyl bromide, 2-(bromomethyl)naphthalene, 4-methylbiphenyl, propane-1,2-diamine, ethane-1,2-diamine, 1,2-diphenylethane-1,2-diamine, rac-BINAP, (R)-BINAP and other ferrocene-based chiral phosphine ligands, sodium tert-butoxide were purchased from Aldrich and Acros and used without further purification, Pd(dba) 2 was synthesized according to the method described.[22] 4-(Bromomethyl)biphenyl was synthesized from 4-methylbiphenyl by a standard procedure using NBS in CCl 4 with AIBN as radical initiator. Bis-formaldehide cyclam and 1,8-dibenzyl cyclam were provided by the CheMatech Co, Dijon, France. Dioxane was distilled over NaOH followed by the distillation over sodium under argon, dichloromethane and methanol were used freshly distilled.Typical procedure for the synthesis of 1,8-bis(arylmethyl) derivatives of cyclam 5, 6.In a one-neck flask (100 ml) bis-formaldehyde-cyclam (1) (2.50 g, 11.2 mmol) was dissolved in 52 ml CH 3 CN, corresponding bromomethyl substituted arene (2-(bromomethyl)naphthalene or 4-(bromomethyl)bipehenyl, 22.4 mmol) was added and the reaction mixture was stirred at room temperature for 72 h. The residue was filtered off, washed with CH 3 CN (3 ˟ 40 ml) and dried in vacuo to obtain di-salts 2 and 3. The deprotection was carried out as follows: di-salt (2 or 3, 5 mmol) was mixed with the aqueous solution of NaOH (8 g in 60 ml) and stirred at 80-90 o C for 48 h. The resulting compound (5 or 6) was taken with CH 2 Cl 2 , dried over anhydrous Na 2 SO 4 , the solvent was evaporated in vacuo to give pure product.1, 8

Pd-Сatalyzed Amination for the Synthesis of Macropolycycles Comprising Cyclen, Cyclam and Naphthalene Moieties

“…We have also shown the possibility to synthesize macrobicycles based on cyclam possessing two naphthylmethyl substituents on the nitrogen atoms of the cryptand. [28] In this communication we report the synthesis of macrobicyclic derivatives of cyclen and cyclam with naphthylmethyl spacers which can be viewed as a valuable and simple chromophore and fluorophore group useful for the creation of macrocyclic chemosensors for metal cations.…”

Pd(0)-Сatalyzed Amination in the Synthesis of Planar-Chiral Macrobicyclic Compounds Comprising 1,5-Disubstituted Anthraquinone Moiety

“…[15] Several years ago we have proposed a direct route to planar-chiral macrocycles using Pd(0)-catalyzed macrocyclization in the presence of chiral phosphine ligands, [16] and further the possibility to synthesize planarchiral macrobicycles comprising cyclam central moiety was also shown. [17] In this connection the present research is aimed at the synthesis of macrobicycles based on the central planar-chiral macrocycle formed around 1,5-disubstituted anthraquinone. Such compounds may be of interest not only due to their chirality but also due to their properties as chromophores and possibility to form chiral complexes with metal cations.…”

Functionalisation of Macroheterocycles with Preserving and Changing Their Sizes

“…This reaction explored chiral diphosphine ligands (198) and (199) based on 1,2-disubstituted ferrocene, and low asymmetric induction was noted (Scheme 41). [107] Cryptand (200) that forms a stable complex with the herbicide paraquat (201) was obtained by the interaction of cis (4,4')-di(carbomethoxybenzo)-30-crown-10 (202) and 2,6-piridinecarboxylic acid dichloroanhydride (203) (Scheme 42). [108] In addition to the above examples of functionalisation of macrocycles that consist in the formation of covalent bonds, there are synthetic methods for compounds with topological bonds that comprise of two or several independent parts not bound with each other by any valence bonds but nevertheless, held together.…”