Úvod do supramolekulární chemie

Living matter processes
1828
O
NH2
H2N
S
H2N
N
O
CH 3
CH 3
COOH
20.000.000 substances
*Transcription of a gene
information
*Secondary and higher
strukture of polypeptides
*Enzymes
*Immune response
Isolated molecules
-synthesis and chemical
behaviour
*hydrogen bonds
*electrostatic interaction
*dispersion forces
*donor/acceptor interactions
*π−π interactions
*cation-π interactions
*solvophobic interaction
Assembly of molecules
Supramolecular chemistry
= non-covalent bond formation
+
1891—Villiers and Hebd: Cyclodextrin inclusion compounds.
1893—Alfred Werner: Coordination chemistry
1894—Emil Fischer: Lock and key concept
1906—Paul Ehrlich: Introduction of the concept of a receptor
1939—Linus Pauling: Hydrogen bonds are included in the groundbreaking book The Nature of the Chemical Bond
1940—M.F. Bengen: Urea channel inclusion compounds
1948—H.M. Powell: X-ray crystal structures of β-quinol inclusion compounds; the term ‘‘clathrate’’ is introduced to
describe compounds where one component is enclosed within the framework of another
1953—Watson and Crick; Franklin and Wilkins: Structure of DNA
1959—Donald Cram: Attempted synthesis of cyclophane charge-transfer complexes with (NC)2C C(CN)2
1964—Busch and Jäger: Schiff’s base macrocycles
1967—Charles Pedersen: Crown ethers
1968—Park and Simmonds: Katapinand anion hosts
1969—Jean-Marie Lehn: Synthesis of the first cryptands
1969—Jerry Atwood: Liquid clathrates from alkyl aluminium salts
1973—Donald Cram: Spherand hosts produced to test the importance of preorganization
1978—Jean-Marie Lehn: Introduction of the term ‘‘Supramolecular Chemistry’’ defined as the ‘‘. . .chemistry of molecular
assemblies and of the intermolecular bond’’
1979—Gokel and Okahara: Development of the lariat ethers as a subclass of host
1981—Vögtle and Weber: Podand hosts and development of nomenclature
1987—Award of the Nobel Prize for Chemistry to Donald J. Cram, Jean-Marie Lehn, and Charles J. Pedersen for their
work in Supramolecular Chemistry
1996—Atwood, Davies, MacNicol, and Vögtle: Publication of Comprehensive Supramolecular Chemistry
1996—Award of the Nobel Prize for Chemistry to Kroto, Smalley, and Curl for their work on the chemistry of the
fullerenes
2003—Award of the Nobel Prize for Chemistry to Agre and MacKinnon for their work on channels in cell membranes.
membranes
t
Bu
O
O
OH
O
O
O
O
O
HO
O
OH
O
n
N
N
H
H
N
N
OH
4-8
spherand
calixarene
preorganizace
crownether
Příklady hostitelských molekul
catenany
Dvojnásobně propletené catenany
Topologická izomerie
rotaxany
katenany
knotany
Molekulární rozpoznání kationtů
Molecular recognition
Defined by: energy
selectivity
• Sterical complementarity (konvexní vs. konkávní)
• Interaction complementarity (pozitivní/negativní)
náboj-dipól, dipól-dipól, akceptor HB-donor HB
• Large contact area (mezi receptorem a substrátem)
• Multiple interactions
Positive x Negative recognition
antibiotikum valinomycin
valinomycin + K+
Chelate and macrocyclic effects
NH3
[Ni(H2O)6]2+ + 6NH3
NH3
[Ni(NH3)6]2+ + 6H2O
NH3
Ni
2+
NH3
NH3
NH3
logK = 8.61 (water)
en =
H 2N
NH2
[Ni(H2O)6]2+ + 3en
[Ni(en)3]2+ + 6H2O
∆G = ∆H – T∆S
o
[Ni(NH3)6]2+ +
4 particles
3en
o
[Ni(en)3]2+ +
NH2
NH2
NH2
Ni
2+
NH2
NH2
NH2
logK = 18.28 (water)
6NH3
7 particles
Macrocyclic effects
O
logKK+ = 2.2
O
O
O
O
O
CH3
CH3
O
O
O
O
O
O
H 3C N
O
O
O
N
O
logKK+ = 6.1
O
CH3
N
O
O
O
O
O
O
N
O
logKK+ = 4.8
logKK+ = 9.75
18-crown-6
Crownethery
1967 C. J. Pedersen (DuPont) - chemie elastomerů
OH
OH
O
OH
O
OH
Cl
Othp
O
O
O
NaOH, ButOH
O
H2O
HO
Dibenzo-18-crown-6
Cl
O
O
O
O
thp
thp
O
O
O
O
O
O
Syntéza crownetherů
Dibenzo-18-crown-6
Dicyklohexano-18-crown-6
18-crown-6
Syntéza crownetherů
high dilution
conditions
LiAlH4
4,13-diaza-18-crown-6
High-dilution conditions
Z
X
cyklizace: vc = kc[X-Y]
Y
X
X
X
+
Y
Z
polymerizace: vp = kp[X-Y]2
Y
Y
vc/vp =
kc[X-Y]
kp[X-Y]2
=
kc
kp[X-Y]
Template effect
Preorganisation effect
log K1(K+), MeOH, 25 °C
O
O
O
CH3
K+
CH3
O
O
little repulsion
2.0 M-1
O
O
O
O
K+
O
O
6.1 M-1
O
O
O
N
O
O
K+
O
O
N
10.0 M-1
lone pair-lone pair repulsion
Solution behaviour
Solid-state behaviour
Solid-state behaviour
log K pro 12-crown-4 až 24-crown-8
S
O
OH
N
N
O
O
O
O
O
O
O
O
O
O
O
O
O
O
S
O
O
N
H
H
N
O
O
O
O
O
O
O
O
Struktura fosfolipidové membrány
Návrh kanálu pro transport kationtů
Iontový kanál
Applications
Phase transfer catalysis
water
O
O
Mn O
O
O
+
K
O
O
O
O
O
O
+
O
K
O
O
O
CHCl3
O
O
O
Mn O
O
Oxidation
KMnO4
Dicyklohexyl[18]crown-6
Benzene
O
O
OH
O
OH
O
Nucleophilic substitution – “naked anions”
CH2 Cl
[18]crown-6
400-500 times faster
CH2
OCOCH3
Chiral resolution
enatiomer-resolving machine
Lariat-ethery
Lariat-ethery
O
O
O
O
O
N
O
OH
N
O
O
O
O
N
OH
+ NaI
+ KI
Lariat-ethery
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
O
N
O
O
O
N
O
O
N
O
O
Kryptandy
Kryptand[2.2.2]
Kryptand[2.1.1]
Kryptand[2.2.1]
Syntéza [2.2.2] kryptandu
O
O
O
Cl
O
Cl
+
H2N
O
O
O
O
High
dilution
O
O
NH
HN
O
NH2
LiAlH4
O
O
O
NH
HN
[2.2.2]kryptand
O
O
High
dilution
O
Cl
N
O
O
O
O
O
O
N
reduction
N
O
O
O
O
O
O
O
N
O
O
O
O
Cl
Kryptandy
Kryptandy
K1(K+), MeOH, 25 °C
O
O
N
O
O
O
N
O
log K1(K+) = 7.0
O
C
N
O
O
N
O
log K1(K+) = 5.4
O
NH
HN
O
O
log K1(K+) = 2.0
Změna konformace [2.2.2] kryptandu
analogicky ke crownetherům
K+
Elektridy (Alkalidy)
[Cs([18]crown-6)2]+.e[Na+([2.2.2]cryptand)].Na-
stabilní několik hodin (298K)
[Li+([2.2.2]cryptand)].e-
rychle se rozkládá nad 230K)
Spherandy
Br
Donald J. Cram
Br
O
O
Li
O
Li
O
BuLi
O
O
Fe(acac)2
Cl-
O
O
O
Li+
O
1) edta
O
O
2) HCl
28%
O
O
O
O
O
O
Spherandy
Li+ komplex
Na+ komplex
Selektivita
Li+/Na+ > 600
Na+/K+ > 1010
Spherandy
Na+/K+ = 13000
Rb+/Cs+ = 134
Li+/Na+ = 360
Na+/K+ = 105
Calixareny
X, R=O-tBu, R1 = tBu
X, R=N(C2H5)2, R1 = tBu
Derivát
Li+
Na+
K+
Rb+
Cs+
X
8.5x105
7.8x109
4.2x106
4.2x105
1.7x106
XI4
1.5x109
8.3x1011
2.3x109
8.5x107
1.2x105
XI6
-
3.2x108
2.4x108
1.4x108
1.3x108
XI8
-
1.6x107
5.0x106
1.0x106
2.9x106
Calixareny
Konické konformery
jsou o několik řádů
horší!!
O
O
K
+
O
O
i-Pr
O O
O
K
O
+
i-Pr
O O
O
i-Pr
i-Pr
K+/Na+ > 105
O
Cs
i-Pr
i-Pr
Na+/K+ > 105
+
O
O O
Cs+/Na+ > 105
(R = i-Pr, octyl)
O
O
R
O
O
O
O
O
+
O O
O
O
O
Na
R
Příspěvek cation-π
interakcí