Chromium trichloride

Alkali metals and especially potassium cause their mixtures to detonate with chromium trifluoride and trichloride. There was also a detonation involving the violent combustion of lithium in contact with chromium trichloride in a nitrogen atmosphere. However, it should be noted that lithium (as well as titanium) is the only alkali metal which can burn in nitrogen. So the chloride implication is not demonstrated in this last case. 

Accidental contamination of lithium strip with anhydrous chromium trichloride or zirconium tetrachloride caused it to ignite and bum vigorously in the nitrogen atmosphere of a glove box. 

Synonyms chromic chloride chromium trichloride chromium sesquichloride. 

Chromium(III) fluoride may be prepared by heating chromium trichloride under a stream of hydrogen fluoride ... 

A solution of the step 1 product (3.85 mmol) dissolved in 40 ml of THF was added to a suspension of potassium hydride (3.85 mmol) in 20 ml of THF and then stirred at ambient temperature for 6 hours. This was then added to a solution of chromium trichloride tris(THF) (3.85 mmol) dissolved in 50 ml of THF. The mixture was stirred at ambient temperature for 12 hours, concentrated, and the residue washed three times with hexane and three times with toluene. The soluble components were dissolved in CH2CI2 and the solution filtered. The filtrate was concentrated, dried under reduced pressure, and 0.969 g of the catalyst isolated. 

As indicated in Scheme 27, indoles may be alkylated by their acid-catalyzed reaction with alcohols. Similarly, r-butylation of pyrroles has been effected by the acid-catalyzed reaction with t- butyl acetate (B-77MI30502), and the diarylmethylation of 1-methylpyrrole from the acid-catalyzed reaction with the chromium trichloride complex of the diarylcarbinol has been described (78JA4124). The alkylation of indoles by alcohols in the presence of the aluminum alkoxide and Raney nickel appears to be efficient for the synthesis of 3-substituted indoles, but is less successful in the alkylation of 2-methylindole (79JHC501). The corresponding isopropylation of pyrrole produces 2,5-diisopropylpyrrole and 1-isopropylpyrrolidine, as the major products (79JHC501). 

As is mentioned in the introductory material, chromium exhibits a propensity to form quadruple bonds that is unmatched by any other first-row transition metaL Although Cr2(02 CQl3)4(H20)2 was first reported over 100 years ago (210), it was not promoted as a quad ruple-bond-containing unit until Cotton and co-workers carried out a redetermination of the x-ray structure and reported a change in the chromium atom separation from the accepted value of 2.64 A initially reported in 1953 (251) to 2.3855(5) A (66, 67). Reduction of chromium trichloride to chromium(II) in aqueous solution with zinc followed by addition of sodium acetate is a convenient route to Cr2(02CCH3)4(H20)2 (204), which can be dehydrated by heating under vacuum to form Cr2(02 CCH3)4. 

Metal Chlorides. Ignites on contact with chromium trichloride or zirconium tetrachloride.8... 

The respiratory system in animals is also a primary target for inhalation exposure to chromium. Pulmonary fluid from hamsters exposed to 0.9 or 25 mg chromium(III)/m3 as chromium trichloride for... 

No hematological abnormalities were found in rats fed diets providing 1,806 mg chromium(III)/kg/day as chromium oxide 5 days/week for 90 days (Ivankovic and Preussmann 1975), or in rats exposed to 3.6 mg chromium(III)/kg/day as chromium trichloride in the drinking water for 1 year (MacKenzie et al. 1958). 

Urinary excretion data from 15 female and 27 male subjects given 200 pg chromium(III) as chromium trichloride indicated that gastrointestinal absorption was at least 0.4% (Anderson et al. 1983). Net absorption of chromium(III) by a group of 23 elderly subjects who received an average of 24.5 pg/day (0.00035 mg chromium(III)/kg/day) from their normal diets was calculated to be 0.6 pg chromium(III)/day, based on an excretion of 0.4 pg chromium/day in the urine and 23.9 pg chromium/ day in the feces, with a net retention of 0.2 pg/day. Thus about 2.4% was absorbed. The retention was considered adequate for their requirements (Bunker et al. 1984). 

The chromium content in major organs of mice receiving drinking water that provided doses of 4.8, 6.1, or 12.3 mg chromium(III)/kg/day as chromium trichloride or 4.4, 5.0, or 14.2 mg chromium(VI)/kg/day as potassium dichromate was determined after 1 year of exposure. Chromium was detected only in the liver in the chromium(III)-treated mice. Mice treated with chromium(VI) compounds had accumulation in all organs, with the highest levels reported in liver and spleen. Liver accumulation of chromium was... 

The distribution of chromium(III) in humans was analyzed using a whole-body scintillation scanner, whole-body counter, and plasma counting. Six individuals given an intravenous injection of 51chromium(III) as chromium trichloride had >50% of the blood plasma chromium(ni) distributed to various body organs within hours of administration. The liver and spleen contained the highest levels. After 3 months, the liver contained half of the total body burden of chromium. The study results indicated a three-compartment model for whole-body accumulation and clearance of chromium(III). The half-lives were 0.5-12 hours for the fast component, 1-14 days for the medium component, and 3-12 months for the slow component (Lim et al. 1983). 

Whole-body analysis of mice given a single intraperitoneal injection of 3.25 mg chromium(III)/kg as chromium trichloride showed that chromium trichloride was released very slowly over 21 days 87% was retained 3 days after treatment, 73% after 7 days treatment, and 45% after 21 days. In contrast, mice given a single intraperitoneal injection of 3.23 chromium(VI)/kg as potassium dichromate retained only 31% of the chromium(VI) dose at 3 days, 16% at 7 days, and 7.5% at 21 days. Mice injected weekly with chromium(III) compounds at 17% of the LD50 retained 6 times the amount of chromium as mice injected with chromium(VI) compounds at 17% of the LD50. The retention of chromium(III) was attributed to its ability to form coordination complexes with tissue components such a proteins and amino acids (Bryson and Goodall 1983). 

Escherichia coli DNA DNA-protein crosslinks No data + Fornance et al. 1981 Chromium trichloride... 

Single-stranded M13mp2 bacteriophange DNA Replication assay increased nucleotide incorporation No data + Snow 1991 Snow and Xu 1989 Chromium trichloride... 

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