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	Hydrogenation - Wikipedia, the free encyclopedia
		The value of varying levels of catalytic activity is that a carefully chosen catalyst can be used to hydrogenate some functional groups without interfering with others, such as the hydrogenation of alkenes without breaking aromatic rings, or the selective hydrogenation of alkynes to alkenes using Lindlar's catalyst.
		In the food industry, an undissolved (or "heterogeneous") metal catalyst is used, such as nickel (often in the form of Raney nickel), or in some very rare cases palladium and platinum.
		In the pharmaceutical industry, and for special chemical applications, palladium and platinum, or in "homogeneous" catalyst such as the rhodium-based compound known as Wilkinson's catalyst, or the iridium-based Crabtree's catalyst are often used.
	en.wikipedia.org /wiki/Hydrogenated (945 words)

	Salt Lake Metals - Precious Metal Chemicals and Compounds
		Collect the catalyst on a buchner funnel and wash it with five 100 ml portions of water and suck dry as possible.
		Transfer the catalyst to a clean, tared specimen tube and dry the catalyst in a drying pistol at 40°C to constant weight (~1-3 h).
		Wash the catalyst thoroughly by decantation with water and finally with dilute acetic acid, collect on a suction filter and wash with hot water until free from chloride or alkali.
	www.saltlakemetals.com /PdCatalystPreparation.htm (1700 words)

	[No title]
		Lindlar's Catalyst (5% Pd on CaCO3, poisoned with Pb) Stir calcium carbonate (precipitated, light; 1.1 g) in water (10 ml) in a flask which is fitted with a thermometer and mounted on a magnetic stirrer/hotplate.
		Transfer the catalyst to a clean, tared, specimen tube and dry the catalyst in a pistol at 40deg.C to constant weight (~ 1-3 h).
		Crush the dry catalyst to a powder with a clean spatula or glass rod and stopper and label the tube (catalyst yield: 0.9-1 g).
	www.intellicandy.com /oldschool/chemcandy/pdcatfaq.txt (1493 words)

	Department of Chemistry, ICSTM: Advanced Organic Chemistry
		Adam's platinum catalyst, with acetic acid as solvent for the substrate, is a powerful combination with which even aromatic rings may be hydrogenated at ordinary temperature and pressure.
		Lindlar's catalyst, additionally poisoned with quinoline, is used to semi-hydrogenate 3-phenylpropyn-3-ol using the macro-scale atmospheric hydrogenator.
		The sterol is hydrogenated with Adam's catalyst in the micro-hydrogenation apparatus.
	origin.ch.ic.ac.uk /local/organic/12.html (2576 words)

	Palladium/Platinum Catalyst Preparation FAQ
		Lindlar's Catalyst (5% Pd on CaCO3, poisoned with Pb) [5]
		The amount of catalyst produced from a given weight of ammonium chloroplatinate is almost exactly ½ the weight of the ammonium salt and is therefore very easily calculated.
		The palladium may be recovered [7,8] as the oxide by evaporating the filtrates to dryness and re-fusing, or as palladium fl by rendering the filtrates slightly alkaline with sodium carbonate and heating with formaldehyde.
	www.erowid.org /archive/rhodium/chemistry/pd-catalyst.faq.html (2548 words)

	Student Doctor Network Forums - OC Question...Alkyne Reduction
		Lindar Catalyst is basically a sheet of metal flat that has the H+ top and the the triple bond thing comes and attaches to the metal sheet; therefore, the only to get reduced is Cis because it is a flat sheet of menta (e.g.
		Lindlar's catalyst (H2/Pd and quinoline) will result in a CIS alkene which is why you may have seen a cis alkene as a possible answer in one of your answer guides.
		The difference between lindlar's catalyst from a plain old Platinum/Palladium catalyst is that lindlars has a 'poison' called Quinoline that limits the reaction from going all the way to an alkane.
	forums.studentdoctor.net /showthread.php?t=174146 (1029 words)

	Lindlars
		After 45 min, the catalyst was removed by filtration and the solvent was removed from the reaction mixture by rotary evaporation.
		Catalytic hydrogenation employing Lindlar's catalyst is a popular method for preparing cis-alkenes from alkynes.
		The explanation for the catalyst's preference for the hydrogenation of alkynes over the hydrogenation of alkenes is thought to involve a reduction in the surface area of available Pd(0) after treatment with the "poison" (Pb(OAc)
	www.alsnotebook.com /lindlars.html (219 words)

	Chemical Reactivity (Site not responding. Last check: 2007-10-11)
		Since alkynes are thermodynamically less stable than alkenes, we might expect addition reactions of the former to be more exothermic and relatively faster than equivalent reactions of the latter.
		This is true for the catalytic hydrogenation reaction; however, the usual Pt and Pd hydrogenation catalysts are so effective in promoting hydrogenation of both double and triple carbon-carbon bonds that the alkene intermediate formed by hydrogen addition to an alkyne cannot be isolated.
		A less efficient catalyst, Lindlar's catalyst, prepared by deactivating (or poisoning) a conventional palladium catalyst by treating it with lead acetate and quinoline, permits alkynes to be converted to alkenes without further reduction to an alkane.
	www.cem.msu.edu /~reusch/VirtualText4/addyne1.htm (2650 words)

	Media Portfolio
		If the catalyst used for the hydrogenation reaction is partially deactivated (poisoned), the reaction can be stopped after the addition of only one mole of hydrogen.
		The catalyst used is commonly known as Lindlar's catalyst and it is composed of powdered barium sulfate coated with palladium poisoned with quinoline.
		Both substrates, the hydrogen and the alkyne, have to be adsorbed on the catalyst for the reaction to occur.
	wps.prenhall.com /wps/media/objects/340/348272/wade_ch09.html (1355 words)

	Chapter 5 - Reduction
		Catalyst activity increases on going to polar, acidic solvents.
		These can also be used to reduce the activity of the catalyst and make it more selective.
		Preferentially bond to the metal surface and thus prevent bonding between catalyst and molecule to be reduced.
	www.chem.uh.edu /Courses/Thummel/Chem6352/Ch05 (702 words)

	TRANSFER HYDROGENATION IN THE REDUCTION OF KETONES
		and examine its use as a transfer hydrogenation catalyst for the reduction of ketones to alcohols, using iso-propanol as the hydride source.
		reducing agents to transfer hydrogen to a metal catalyst is therefore of interest.
		) and examine its use as a transfer hydrogenation catalyst for ketones.
	www.ch.ic.ac.uk /local/organic/8-h2.html (272 words)

	CHM 201 H - 2nd Examination - 31 Oct 2001 (Site not responding. Last check: 2007-10-11)
		Of the following, the one that does not produce a ketone on hydration with water, mercuric sulfate, and acid is:
		On catalytic hydrogenation over the Lindlar catalyst, 1 equivalent of H
		are absorbed on hydrogenation with a palladium catalyst?:
	www.miami.edu /chem/chm201c/201c31oct01/20131oc0.htm (864 words)

	Year 1997: ORGLIST: Re: Pd as a Catalyst (Site not responding. Last check: 2007-10-11)
		When Pd on Carbon is used as a catalyst for a hydrogenation reaction,
		Catalyst is that when it is used to treat an alkyne, it will result in an
		The Lindlar Catalyst is important for synthesizing certain cis
	www.orglist.net /archive/1997/0080.html (169 words)

	[No title] (Site not responding. Last check: 2007-10-11)
		To convert 1-butyne to 2-butanol, use a) H2 and the Lindlar catalyst; then H+ and H2O b) BH3 in THF; then H2O2 and OH- c) H2 and Pd on charcoal; then Hg(OAc)2, H2O, THF; then NaBH4 d) H2O, H2SO4, and Hg(SO4) e) Li in NH3; then BH3 in THF; then H2O2 and OH- 14.
		To convert propyne to cis-2-butene use: a) Br2 in CCl4, then H2 with the Lindlar catalyst, then CH3-Br b) H2 with the Lindlar catalyst, then KOH, then CH3-Br c) BH3 in THF, then CH3MgBr d) NaNH2, then CH3-Br, then H2 and the Lindlar catalyst e) Li in NH3, then HBr, then CH3-Br 16.
		To convert propyne to 1,1-dichloro-2-methylcyclopropane use: a) H2 and the Lindlar catalyst, then CHCl3 and KOH b) Cl2, then H2 and Pt, then CH3-Cl c) BH3, then H2 and the Lindlar catalyst, then NaNH2 and CHCl3 d) H2 and Pd on carbon, then CH3-Br and KOH e) NaNH2, then CH3-Cl, then KOH 17.
	www.miami.edu /chem/chm201c/20125oc0.htm (1055 words)

	[No title] (Site not responding. Last check: 2007-10-11)
		Hydrogenation of an alkyne with one equivalent of hydrogen and the Lindlar catalyst (a specially deactivated catalyst) reduces the alkyne to an alkene.
		The addition proceeds with syn stereochemistry, so the alkene is cis if the starting alkyne is not at the end of the chain.
		The carbons of the triple bond are green and the added hydrogens are blue.
	www.du.edu /~jhornbac/organic/pg445.html (79 words)

	New Page 1
		A versatile hydrogenation catalyst can carry out almost all types of hydrogenation reactions.
		A powerful hydrogenating catalyst Useful where the reaction conditions are mild acidic in nature.
		Used as a in-situ hydrogenation catalyst at ambient pressure (Open Vessel hydrogenation).
	www.vineethchemicals.com /product_List.htm (358 words)

	Alkyne Reductions to Alkenes - EMOC (Site not responding. Last check: 2007-10-11)
		Use of an inactivated transition metal catalyst such as the Lindlar catalyst (Pd/CaCO3) will result in Z-alkenes whereas use of an alkali metal such as sodium dissolved in ammonia will result in E-alkenes.
		Reduction of alkynes with the Lindlar catalyst follows the same mechanism as the reduction of alkynes or alkenes with transition metal catalysts.
		Use of a deactivated catalyst simply does not reduce alkenes to alkanes, but stops after reduction of the alkyne to the alkene.
	www.chem.memphis.edu /parrill/EMOC/roadmap/ynered.html (214 words)

	Organic Chemistry 341 Notes
		Reduction with hydrogen and a metal catalyst usually gives the fully saturated alkane.
		Using a special deactivated catalyst, Lindlar's Catalyst, the reduction can be stopped at the alkene stage giving cis double bonds.
		Trans double bonds can be obtained using lithium or sodium metal dissolved in ammonia.
	www.ndsu.nodak.edu /instruct/grcook/chem341_98/lectures/lecture22.shtml (78 words)

	[No title] (Site not responding. Last check: 2007-10-11)
		The alkene is the intermediate of the first step, which undergoes more hydrogenation to form alkane.
		The product of hydrogenation with Lindlar’s catalyst is a cis-alkene (syn addition).
		The catalyst for hydration is H2SO4 and HgSO4 (only H2SO4 for hydration of alkenes).
	users.ipfw.edu /tahmassd/CHM261/Chapter-9-Notes.doc (2044 words)

	Platinium/Palladium Catalyst On Activated Charcoal/On Barium Sulphate/On Calcium Carbonate Suppliers & ...
		Platinium/Palladium Catalyst On Activated Charcoal/On Barium Sulphate/On Calcium Carbonate
		Maharashtra, India Nickel Aluminium powder, Raney nickel Catalyst, 1%,3%,5%,10% Platinium/Palladium Catalyst on Activated Charcoal/on Barium Sulphate/on Calcium Carbonate, Lindlar Catalyst.
		1 to 1 of 1 platinium/palladium catalyst on activated charcoal/on barium sulphate/on calcium carbonate suppliers
	www.chemicalregister.com /Platinium/Palladium_Catalyst_On_Activated_Charcoal/On_Barium_Sulphate/On_Calcium_Carbonate/Suppliers/pid11140.htm (79 words)

	[No title] (Site not responding. Last check: 2007-10-11)
		Hydrogen gas in the presence of Pt or Pd, deposited on charcoal, will completely reduce the alkyne to give the alkane.
		Hydrogen gas in the presence of Lindlar Catalyst, or Pt or Pd, deposited on barium sulfate, will partially reduce the alkyne to give the cis-alkene.
		Lithium metal dissolving in liquid ammonia (a dissolving metal reduction) will reduce an alkyne by a stepwise addition of electrons to give the trans-alkene as product.
	www.chem.uic.edu /web1/OCOL-II/WIN/ALKENE/92/92CANS.HTM (181 words)

	Chem 3010
		But with the metal catalysts used for alkenes, this reaction will continue: -HC=CH- + H
		C-CH If it is desired to stop at the alkene stage, a Lindlar catalyst prevents further reaction of the C=C
		(In contrast, the catalyst in the H
	science.csustan.edu /almy/3010/McM5Chapters/5mcm08.htm (1462 words)

	IngentaConnect Obtaining 1-heptene from 1-heptyne semihydrogenation with an anch...
		Obtaining 1-heptene from 1-heptyne semihydrogenation with an anchored rhodium complex on different supports as catalyst
		Results determined by the latter technique suggest that the active species is the complex itself, which is stable under the reaction conditions.
		The supported rhodium tetra-coordinated complex shows higher activity and selectivity than the same complex unsupported, and also than the classic Lindlar catalyst.
	www.ingentaconnect.com /content/jws/jctb/2005/00000080/00000002/art00007 (284 words)

	Organic Chemistry II: Nitroglycerine synthesis
		This is a nitrate ester made by esterification.
		In this process, glycerols reacts with Nitric Acid under a catalyst of Sulphuric Acid at 300oC to yield an ester complex of glyceryl trinitrate otherwise known as nitroglycerine, and three water molecules.
		In this process, there has been formation of an ester bond (COO).
	chem242.blogspot.com /2005/07/nitroglycerine-synthesis.html (331 words)

	Alkynes + H2 (Site not responding. Last check: 2007-10-11)
		The reaction is stereospecific giving only the syn addition product.
		The "poisoned" catalyst prevents over-reduction, which would give the alkane by reducing the alkene
		Alkyne approaches the H atoms absorbed on the metal surface.
	www.chem.ucalgary.ca /courses/351/Carey/Ch09/ch9-6.html (95 words)

	Model of (Z)-Hex-2-ene (cis-2-Hexene)
		Adding two hydrogen atoms to the same side of an acetylene triple bond (syn addition) leads to the cis-alkene.
		This can be carried out in practice by using a partially deactivated metal catalyst (such as Lindlar's catalyst.)
		To rotate: press left mouse button on molecule and drag
	wps.prenhall.com /wps/media/objects/340/348697/hex-2-ene-z.html (66 words)

	[No title]
		The hyperlinks in the table compile a list of all articles containing these keywords from the Basic Keyword List.
		The Lindlar Catalyst Revitalized: A Highly Chemoselective Method for the Direct Conversion of Azides to N-(tert-Butoxycarbonyl)amines
		/ Lindlar catalyst / Azides / Chiral ligands / Synthetic methods / Reduction /
	www.wiley-vch.de /cgi-bin/search_key.pl?p=1&sf=key&a1=chemoselectivity (225 words)

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