CeCl3, Cerium chloride

Cerium(ill) chloride heptahydrate Cerium chloride (CeCl3), heptahydrate (18618-55-8), 76, 228... 

Reaction of anhydrous cerium(iii) chloride with RLi reagents affords organocerium compounds The cerium chloride is prepared by heating CeCl3(H20)7 in vacuo up to 140 °C and is in fact a monohydrate [CeCl3(H20)], see W.J. Evans, J.D. Feldman, and J.W. Ziller, J. Am. Chem. Soc., 1996,118,4581. Reaction is carried out at -78 °C, as decomposition is rapid at 0 °C, especially if a /3-hydrogen is present in the R group. The exact nature of the cerium species is uncertain. 

Cerium chloride (CeCl3 7H20) in the presence of Nal catalyzes the diastereoselective dehydration of P hydroxyketones and esters such as 4.8 to the corresponding a, (3-unsaturated compound 4.9. 

Cerium(lll) chloride monohydrate Cerium chloride (CeCl3), monohydrate (10) ... 

Cerium(m) chloride could mediate high-yielding additions of /V-bcnzyl- ,/V-dilithio methanesulfonamide 12 to aldehydes and ketones of biologically importance (Scheme 5).9 Excess amount of CeCl3 (8.2 equiv.) afforded the adduct in excellent yield, while lower yield of the adduct was obtained in the absence of CeCl3. 

Hydrates of rare earth chlorides also have two different crystal systems a triclinic system for lanthanum, cerium, and praseodymium, as well as a monoclinic system for neodymium to lutetium and yttrium. CeCl3-7H20, as an example of the former system, is different from the above infinite polymer as two cerium atoms are connected by two [i2-bridges to form a dimer. The formula for this dimer is [(H20)7Ce([i2-Cl)2Ce(H20)7]Cl4 as shown in Figure 1.18. Therefore, the coordination number of cerium is nine and the polyhedron takes on a destroyed mono-capped square antiprism configuration. 

When the resulting cerium(lll) chloride (730-779 mg) is dissolved in 10 mL of dry methanol, Karl Fischer analysis of the solution shows that the cerium(tll) chloride contains 6.5-7.6% of water which is equal to 95-113% of the water expected from the formula CeCl3-H20. 

Karl Fischer titration of a dry methanol solution (15 mL) of the resulting cerium(lll) chloride (731-817 mg) shows that it contains 0.71-0.94% of water and can be represented by a formula CeCl3(H20)o.io-0.i3- This result indicates that this procedure affords practically anhydrous cerium(lll) chloride, although Evans, et al. reported that gradual heating to 150°C at 0.03 mm over 3 hr, followed by further... 

Cerium(lll) chloride heptahydrate CeCl3-7H30 18618-66-8 372.682 yel orth cry hyg 90 dec vs H,0, EtOH... 

Cerium(III) chloride CeCl3 +2490 Dysprosium(III) oxide Dy203 +89600... 

To a solution of 100 mg (2R)-2-((lR)-hydroxy-l-hept-3-yn-2-one)-l-[((15, 2R)-2-(1-methyl- 1-phenylethyl) cyclohexyoxy) carbonyl]-5-(triisopropylsilyl)-2,3-ciihydro-4-pyridone (0.161 mmol) in 7 mL methanol was added 66 mg cerium(III) chloride heptahydrate (CeCl3 7H20, 0.177 mmol) in one portion. After being stirred for 10 min, the mixture was cooled to —50°C, and 9 mg sodium borohydride (0.241 mmol) was added. The reaction mixture was stirred for an additional 10 min, quenched with 10 mL water, and extracted with CH2CI2 (3 x 10 mL). The combined extracts were dried over MgS04 and concentrated under reduced pressure. The residue was purified by radial PLC (silica gel, 30% EtOAc/hexanes) to give 96 mg (2R)-2-((lR,25)-dihydroxy-hept-3-yne)- -[((15,2R)-2-( 1-methyl- 1-phenylethyl)-cyclohexyloxy)carbonyl]-5-(triisopropylsilyl)-2,3-dihydro-4-pyridone as a colorless oil, in a yield of 96%. 

Cerium(III) chloride CeCl3 -1-2490 Dysprosium(III) sulfide Dy2S3 -r95200... 

For the first time a naturally occurring coumarin, namely, ocimarin 56, was synthesized using cerium (III) chloride heptahydrate catalyzed under solvent-free conditions in three steps with 23.2% total yield.The steps involve the protection of 2-bromoethanol by standard tetrahydropyranylation (DHP, CeCl3 7H20) in 95.1% yield, which was alkylated with (EtONa, reflux, EtOH) to afford compound 55 in 40.3% yield. Then 55 reacted with resorcinol via a Pechmann reaction to give 56 in 56.8% yield (Scheme 39) (10MI1165). 

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