Samarium salts

The use of two-valence samarium salts is a radically new approach both for CCl3Br and CBr4, which actively initiate these reactions under mild conditions (ref. 4) ... 

Samarium salts are used in optical glass, capacitors, thermoionic generating devices, and in sensitizers of phosphors. The metal is doped with calcium fluoride crystals for use in lasers. It also is used along with other rare earths for carbon-arc lighting. Its alloys are used in permanent magnets. 

Samarium sesquioxide is used in optical and infrared absorbing glass to absorb infrared radiation. Also, it is used as a neutron absorber in control rods for nuclear power reactors. Tbe oxide catalyzes dehydration of acychc primary alcohols to aldehydes and ketones. Another use involves preparation of other samarium salts. 

Samarium Polyvanadates.—Addition of a neutral samarium salt to a solution of a metavanadate throws down a yellow, amorphous precipitate which consists mainly of samarium orthovanadate. Two acid... 

SYNS ACETIC ACID, SAMARIUM SALT SAMAR-... 

In an even more simple approach, the reductive samariation of the readily available anomeric acetates 213 is possible in the absence of any additive that increases the reducing power of the samarium salt [100] (O Scheme 44). 

Use Catalyst in the dehydrogenation of ethanol, infrared-absorbing glass, neutron absorber, preparation of samarium salts. 

Disamarium trioxide EINECS 235-043-6 Samaria Samarium (III) oxide Samarium oxide Samarium oxide (Sm203) Samarium sesquioxide Samarium trioxide Samarium(3 ) oxide Samarium(lll) oxide. Catalyst in the dehydrogenation of ethanol, infrared-absorbing glass, neutron absorber, preparation of samarium salts. Solid d -8.347. Noah Chem. Rhdne-Poulenc. 

A soln. of benzaldehyde and 5% SmClj in DMF electrolyzed (apparent current density 0.4-0.5 A/dm ) in a one-compartment cell fitted with a nickel or stainless steel cathode and a sacrificial Mg anode at 20° for 5-18 h, and hydrolyzed with acid - product. Y SOVo. This is the first use of a samarium salt in catalytic amount for pinacol-type coupling the method is applicable to aliphatic and aromatic oxo compds. F.e. inch intramolecular coupling s. E. Leonard et al., J. Chem. Soc. Chem. Commun. 1989, 276-7. 

In comparison to samarium and ytterbium salts, there were few examples for cerium, praseodymium, and other the rare earth metals catalyzed aldol reaction (214,215). In 2000s, Samarium salts, especially Sml2, have been used in versatile aldol reactions, for example, direct aldol of aldehydes and substituted oxi-ranyl ketones (216), nitro aldol reaction (217,218), intramolecular aldol reaction (219), and other aldol reaction of special carbonyl compounds (220-222). However, catalytic asymmetric samarium-catalytic aldol reaction was not reported so far. In the asymmetric version of the aldol reaction, ytterbium exhibited promising enantioinduction. In the first example of the asymmetric ytterbium-catalyzed aldol reaction, moderate levels of enantioselectivities were achieved (Scheme 56) (223). Subsequently, Mlynarski and co-workers improved enatioinduction ability of the ytterbium-catalyzed aldol reaction by using catalytic amount of Yb(OTf)3... 

Samarium salts react with sodium tungstate to form samarium tungstate which fluoresces red. 

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