Solving Zeolite Jigsaw:

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Blanche McCarthy
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1 Solving Zeolite Jigsaw: A Synthetic Chemist's Approach R. Murugavel Dept. of Chemistry, IIT-Bombay rmv@chem.iitb.ac.in muruks@iitb.ac.in Tel. 7163

2 ur major research efforts: Solving the Zeolite Jigsaw (or) Rational Synthesis of orous Solids M n+ Aminobenzoic acids olycarboxylic acids hosphorus based acids Silanols

3 What are zeolites? orous crystalline solids Greek, zein, "to boil ; lithos, "stone Discovered by Cronstedt in 1756 Zeolite origin: as volcanic ash that is spewed into the atmosphere during violent eruptions. B.C., Roman Aqua Ducts of ure Water

4 History of zeolites Cronstedt (1756): Damour (1840): Grandjean (1909): Weigel and Steinhoff (1925): MacBain (1926) : Milton, Union Carbide (1949) Certain minerals produce steam on heating and they dance during the process Zeolites could be reversibly dehydrated Dehydrated zeolites absorb other small molecules Chabazite absorbs MeH, EtH, or HCH, but not acetone, ether, or benzene Explained the above process as molecular differentiation at 5 Å (0.5 nm) without the loss of space lattice About 30 papers on separation of branched olefins from linear olefins and polar moelcules from non-polar molecules. Worlds first man-made Zeolites.

5 Today s zeolite science and technology? 1 Domestic Water purification 2 etrochemical industry Brǿnsted Acid Catalysts 3 Gas Separation 4 uclear Industry 5 Agriculture 6 Animal Welfare 7 Medical 8 Heating and refrigeration 9 Detergents 10 Construction roblem of supply versus demand eed for newer, tailored zeolites!

6 Why more Zeolites! CH 3 CH 3 CH 3 CH 3 CH 3 CH 3 Similar boiling points (144, 138, and C), but large size difference

7 Kitchen Sieve!

8 Molecular Sieve!

9 Zeolite synthesis A + B + C + D + E +.. A new zeolite (once in a while!)

10 Rational zeolite synthesis? Replace this By this! In other words, a brick by brick building approach

11 Lego Blocks

12 Lego City Chicago

13 Zeolitic Structures Is Lego approach applicable to Zeolite science? Scandinavian Connection!

14 What would this mean?

15 Look closer!???????????

16 Build up of Zeolite Cages Si 4-ring (4R) or 6-ring (6R)

17 Lego bricks of Zeolite Science? H H H Si H H H H Challenge? : Design of Suitable recursors Zeolites are originally aluminosilicates. In 1982, this was expanded to include aluminophosphates.

18 The Choice? Two rganophosphates! R R H H R H Inorg. Chem. 2001, 40, 1084 Inorg. Chem. 2002, 41, 6404 Inorg. Chem. 2004, 43, 945 Inorg. Chem. 2004, 43, 7585 Inorg. Chem. 2005, 44, 6314 Chem. Commun. 2003, 2546 Acc. Chem. Res. 2004, 37, 763

19 Moving ahead. Mono-esters? H H Ability to form Cage Structures

20 A Versatile Building Block - Across the eriodic Table Chem. Euro. J. 2009, in press R = i r Also see: R. Murugavel et al. Chem. Rev. 2008, 108, R. Murugavel, Chem. Soc. Rev. 2009, to appear

21 Seeking double-ring structures R H H + (Ac) 2.2H 2 MeH L R R L R L L R L=MeH collidine R R R R Insoluble, but not a layered solid. What is the proof for the D4R structure? Yield 85 %; δ( 31 ) = -4.5 ppm Soluble Compound roof for D4R comes from spectroscopy and X-ray diffraction Yield 68 %; δ( 31 ) = -4.7 ppm

22 First Molecular hosphate that Resembles D4R Has been found in several framework phosphates But never been isolated in simple D4R molecular form

23 2-Aminopyridine, the linker Two H 2 groups form both inter- and intramolecular H-bonds The other two H 2 groups form only intramolecular H-bonds Hence 1-D chain of D4R blocks A perfect 1-D assembly of D4R Cages

24 RM, SK, RB, AS Angew. Chem., Int. Ed. 2006, 45(33),

25 3D H-bonded Structures ~ 2 nm IIT-B Legoland is closer! Chemistry Euro J in press

26 Back to covalent approach! (Ac) 2.2H 2 + R()(H) 2 + 4,4'-bipyridine R R R R

27 (Ac) 2.2H 2 + R()(H) 2 + 4,4'-bipyridine R R R R 4:4:2 M : phosphate: bpy

28 R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R Crystal Structure of M 4 (R 3 ) 4 (bpy) 2.4H 2.DMF R. Murugavel & S. Kuppuswamy (unpublished) IIT-B Legoland achieved

29 Change of stoichiometry and the guest L R R 1.5 eq 4,4'-bipyridine L R DMS L L R L=MeH R. Murugavel & S. Kuppuswamy (unpublished)

31 More recent!

32 ayanmoni Gogoi, Sept (unpublished) Getting closer to ature!

33 Acknowledgements + all alumni of the group IRCC This is a tough Synthetic challenge. The credit to all co-workers

Inorganic Material chemistry

Inorganic Material chemistry Silicone -Inorganic Polymer Polymer poly + mer many units Basic unit is called repeat unit (monomer) A polymer is a large molecule (macro molecule) composed of repeating structural