Synthesis and X-ray Structure of the Inclusion Complex of Dodecamethylcucurbit[6]uril with 1,4-Dihydroxybenzene

Abstract

Abstract:The synthesis, and X-ray crystal structure of the inclusion host-guest complex of dodecamethylcucurbit [6]uril (DDMeQ[6]) with 1,4-dihydroxybenzene (DHOBEN) are reported. The complex crystallizes in the space group P21/c (No.14) with a =12.2847(4), b = 12.6895(4), c = 15.1310(4) Å, α = 74.6960(10), β = 71.4090(10), γ = 86.5090(10)° and Z = 1. A novel approach to dodecamethylcucurbit[6]uril synthesis is also described. To separate dodecamethylcucurbit[6]uril, 1,4-dihydroxybenzene is used as a guest molecule for crystallization of the fully methyl-substituted cucurbituril. The driving force for the self-assembled inclusion host-guest complex can be attributed to not only the cavity interaction of dodecamethylcucurbit[6]uril (host), but also to the hydrogen bonding between the carbonyl oxygen at the portals of the host and the hydroxy groups of the guest.

Cucurbit[n]uril‐Based Supramolecular Frameworks Assembled through Outer‐Surface Interactions

“…[96] Thed iversity of the OSIQ-induced QSFs also originates from the many members of the Q[n]family,from the smallest Q [4] analogues [29,30] to the largest twisted Q [15]. [31] Moreover, the Q[n]c omponents also range from unsubstituted Q-[n]s, [32][33][34][35][36] Q[n]a nalogues,Q [ n]d erivatives, [37][38][39][40] and various alkyl-substituted Q[n]s, [41][42][43][44][45][46][47][48][49][50][51][52][53] to fully and partially hydroxylated Q[n]s and semi-Q[n]s. [28] These species were used to construct numerous OSIQ-induced QSFs in different media and by different synthetic methods.T hus,t he study of the OSIQ-induced QSFs and their functional properties is an expansive research subject.…”

“…Generally,t he value of "n"d etermines the size of the cavity and portals of aQ [ n]. At present, the members of the Q[n] family range from the smallest Q[n]analogues,Q [4]s, [29,30] to the largest, Q [15],w hich has at wisted structure, [31] unsubstituted Q[n]s, [32][33][34][35][36][37][38][39][40] and av ariety of fully and partially alkylsubstituted Q[n]s. [41][42][43][44][45][46][47][48][49][50][51][52][53] In total, there are over ah undred cucurbit [n]urils and analogues known at the present time. [28] Figure 1s hows the X-ray crystal structures of representative Q[n]s along with plots of the calculated electrostatic potentials of the surfaces of the Q[n]s.T he electrostatic potentials show that:1 )their two open portals have negative electrostatic potential since they are rimmed with carbonyl oxygen atoms;2 )their inner-cavity surfaces have almost neutral electrostatic potential, and 3) their outer surfaces have positive electrostatic potential (Figure 1bottom).…”

Molecular Sensing with Host Systems for Hyperpolarized 129Xe

“…Furthermore, it might provide a handle that is amenable to functionalization [ 276 ]. This led to the generation of substituted CB[n]s such as cyclohexane-substituted (CyH) n CB[n]s (CyH = cyclohexano; n = 5–8 [ 277 ]), Me 12 CB[6] (Me = methyl [ 278 , 279 ]), (CyP) n CB[n] (CyP = cyclopentano [ 280 ]), Ph 2 CB[6] (Ph = phenyl [ 281 ]), HMeCB[6] (H = hexa [ 282 ]), TMeCB[6] (T = tetra [ 283 ]), (CyH) 2 CB[6] [ 284 ] and (Me 2 CyP) n CB[6] [ 278 ], respectively. Among the different substituted CB[n]s, the cyclohexane-based derivatization of the CB[n] (n = 5–8, CyH n CB[n]s) rendered them more soluble in both water and certain organic solvents.…”

Cucurbit[n]uril‐Based Supramolecular Frameworks Assembled through Outer‐Surface Interactions

“…Generally, the value of “ n ” determines the size of the cavity and portals of a Q[ n ]. At present, the members of the Q[ n ] family range from the smallest Q[ n ] analogues, Q[4]s, [29, 30] to the largest, Q[15], which has a twisted structure, [31] unsubstituted Q[ n ]s, [32–40] and a variety of fully and partially alkyl‐substituted Q[ n ]s [41–53] . In total, there are over a hundred cucurbit[ n ]urils and analogues known at the present time [28] .…”