Three closely-related cyclohexanols (C₃₅H₂₇X₂N₃O₃;X= F, Cl or Br): similar molecular structures but different crystal structures

Abstract

Three highly-substituted cyclohexanol derivatives have been prepared from 2-acetylpyridine and 4-halogenobenzaldehydes under mild conditions. (1RS,2SR,3SR,4RS,5RS)-3,5-Bis(4-fluorophenyl)-2,4-bis(pyridine-2-carbonyl)-1-(pyridin-2-yl)cyclohexanol, C35H27F2N3O3, (I), (1RS,2SR,3SR,4RS,5RS)-3,5-bis(4-chlorophenyl)-2,4-bis(pyridine-2-carbonyl)-1-(pyridin-2-yl)cyclohexanol acetone 0.951-solvate, C35H27Cl2N3O3·0.951C3H6O, (II), and (1RS,2SR,3SR,4RS,5RS)-3,5-bis(4-bromophenyl)-2,4-bis(pyridine-2-carbonyl)-1-(pyridin-2-yl)cyclohexanol, C35H27Br2N3O3, (III), all crystallize in different space groups, viz. Pbca, Fdd2 and P1, respectively. In compound (II), the acetone molecule is disordered over two sets of atomic sites having occupancies of 0.690 (13) and 0.261 (13). Each of the cyclohexanol molecules contains an intramolecular O-H···N hydrogen bond and their overall molecular conformations are fairly similar. The molecules of (I) are linked by two independent C-H···O hydrogen bonds to form a C(5)C(10)[R2(2)(15)] chain of rings, and those of (III) are linked by a combination of C-H···O and C-H···N hydrogen bonds, forming a chain of alternating R2(2)(16) and R2(2)(18) rings. The cyclohexanol molecules in (II) are linked by a single C-H···N hydrogen bond to form simple C(4) chains and these chains are linked by a π-π stacking interaction to form sheets, to which the disordered acetone molecules are weakly linked via a number of C-H···O contacts.

Synthesis of Terpyridines: Simple Reactions—What Could Possibly Go Wrong?

“…In addition to the parent compound (Ar = Ar 1 = C 6 H 5 ) [39,40,41,42,43,44,45,46], a large number of derivatives with carbocyclic Ar and Ar 1 substituents have been obtained from reactions of substituted benzaldehydes and acetophenones [34,41,43,46,47,48,49,50,51,52,53]. Of most relevance to the chemistry reported in this manuscript, are compounds with heterocyclic substituents and, to date, examples with thiophen-2-yl [34,41,54,55,56], furan-2-yl [54,57], benzofuran-2-yl [33], benzofuran-3-yl [33], benzothiophen-2-yl [33], benzothiophen-3-yl [33], pyridin-2-yl [33,35,45,58,59,60,61,62,63,64,65,66] pyridin-3-yl [33,45,56] and pyridin-4-yl [16,20,33,45,56,67] groups have been reported. Cave and Raston have commented that reactions of 4-acetylpyridine with 4-alkoxybenzaldehydes in solution only yield the 3:2 products rather than the desired 4,2′:6′,4″-terpyridines [16,20].…”

The crystal structures of two chalcones: (2E)-1-(5-chlorothiophen-2-yl)-3-(2-methylphenyl)prop-2-en-1-one and (2E)-1-(anthracen-9-yl)-3-[4-(propan-2-yl)phenyl]prop-2-en-1-one

“…Chalcones, R 1 -C( O)-CH CH-R 2 , are versatile intermediates in synthesis (Baktır et al, 2011;Samshuddin et al, 2011Samshuddin et al, , 2012Samshuddin et al, , 2014Nayak et al, 2014;Salian et al, 2015;Mohan et al, 2016). Compounds of this class also exhibit a wide range of biological activity, including anti-bacterial (Tran et al, 2012), anti-cancer (Syam et al, 2012;Kumar et al, 2014), antifungal (Ló pez et al, 2001), anti-inflammatory (Fang et al, 2015), anti-malarial (Agarwal et al, 2005) and antitubercular activities (Dimmock et al, 1999).…”