TY - JOUR

T1 - Topological polymorphism and temperature-driven topotactic transitions of metal-organic coordination polymers

AU - Dubskikh, Vadim A.X.

AU - Lysova, Anna A.

AU - Samsonenko, Denis G.

AU - Dybtsev, Danil N.

AU - Fedin, Vladimir P.

PY - 2020/10/14

Y1 - 2020/10/14

N2 - Two metal-organic frameworks (MOFs), [Mg3(btdc)3(dmf)4]·DMF (1) and [Mg3(btdc)3(dmf)4] (2) (H2btdc = 2,2′-bithiophene-5,5′-dicarboxylic acid; dmf = N,N-dimethylformamide), were synthesized from a similar reaction mixture at 80 °C or 130 °C, respectively. Both compounds are based on {Mg3(RCOO)6} trinuclear carboxylate units, serving as 6-connected nodes of the corresponding 3D frameworks. The low-temperature phase (1) adopts the frequent primitive-cubic (pcu) topology, while the high-temperature phase (2) crystallizes in the very rare sxb topology. The heating of 1 results in a facile solid-state phase transition into 2 both in DMF solvent and under solvent-free conditions, involving a significant rearrangement of bulky bithiophenedicarboxylate anions in a regular fashion. The detailed analysis of the crystal structures of both polymorphs reveals possible reaction sites and provides valuable insights into such an unprecedented topotactic process.

AB - Two metal-organic frameworks (MOFs), [Mg3(btdc)3(dmf)4]·DMF (1) and [Mg3(btdc)3(dmf)4] (2) (H2btdc = 2,2′-bithiophene-5,5′-dicarboxylic acid; dmf = N,N-dimethylformamide), were synthesized from a similar reaction mixture at 80 °C or 130 °C, respectively. Both compounds are based on {Mg3(RCOO)6} trinuclear carboxylate units, serving as 6-connected nodes of the corresponding 3D frameworks. The low-temperature phase (1) adopts the frequent primitive-cubic (pcu) topology, while the high-temperature phase (2) crystallizes in the very rare sxb topology. The heating of 1 results in a facile solid-state phase transition into 2 both in DMF solvent and under solvent-free conditions, involving a significant rearrangement of bulky bithiophenedicarboxylate anions in a regular fashion. The detailed analysis of the crystal structures of both polymorphs reveals possible reaction sites and provides valuable insights into such an unprecedented topotactic process.

KW - SINGLE-CRYSTAL

KW - SUPRAMOLECULAR ISOMERISM

KW - BOND REARRANGEMENT

KW - PHASE-TRANSITION

KW - FRAMEWORK

KW - INTERPENETRATION

KW - ADSORPTION

KW - TRANSFORMATIONS

KW - FLEXIBILITY

KW - EXAMPLE

UR - http://www.scopus.com/inward/record.url?scp=85092411065&partnerID=8YFLogxK

U2 - 10.1039/d0ce01045f

DO - 10.1039/d0ce01045f

M3 - Article

AN - SCOPUS:85092411065

VL - 22

SP - 6295

EP - 6301

JO - CrystEngComm

JF - CrystEngComm

SN - 1466-8033

IS - 38

ER -