101-41-7 A NOVEL AND USEFUL METHOD FOR THE PREPARATION OF METHYL ESTERS FROM DIMETHYL ACETALS

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In the presence of a catalytic amount of trityl perchlorate, acetal-type peroxides are successfully prepared from dimethyl acetals and t-butyl trimethylsilyl peroxide in good yields.The peroxides thus obtained are converted to the corresponding methyl esters also in good yields. https://www.lookchem.com/CASDataBase_101-41-7.htm

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1023-17-2 Syntheses, structures, and catalytic activity in Friedel–Crafts acylations of substituted tetramethylcyclopentadienyl molybdenum carbonyl complexes

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Reactions of the substituted tetramethylcyclopentadienes [C 5 HMe 4 R] [R?=? t Bu, Ph, CH 2 CH 2 C(CH 3 ) 3 ] with Mo(CO) 3 (CH 3 CN) 3 in refluxing xylene gave a series of dinuclear molybdenum carbonyl complexes [(η 5 -C 5 Me 4 R)Mo(CO) 3 ] 2 [R?=? t Bu (1), Ph (2), CH 2 CH 2 C(CH 3 ) 3 (3)], [(η 5 -C 5 Me t Bu)Mo(μ-CO) 2 ] 2 (4)], and [(η 5 -C 5 Me 4 ) t Bu] 2 Mo 2 O 4 (μ-O) (5)], respectively. Complexes 1–5 were characterized by elemental analysis, IR, 1 H NMR, and 13 C NMR spectroscopy. In addition, their crystal structures were determined by X-ray crystal diffraction analysis. The catalytic activities of complexes 1–3 in Friedel–Crafts acylation in the presence of o-chloranil has also been investigated; the reactions were achieved under mild conditions to give the corresponding products in moderate yields. https://www.lookchem.com/CASDataBase_1023-17-2.htm
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7440-47-3 Influence of pulse plating on the crystal structure and orientation of chromium

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Chromium deposits with various structures and orientations were prepared by pulse plating from a sulfate-catalyzed chromic acid solution and without formic acid addition. The influences of the puls duration, off-time, curent density, formic acid concentration, and plating time on the structure and orientation were studied by X-Ray diffraction and transmition electron microcsopy. https://www.lookchem.com/CASDataBase_7440-47-3.htm
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75-01-4 Nickel(I) Octaethylisobacteriochlorin Anion. An Exceptional Nucleophile. Reduction and Coupling of Alkyl Halides by Anionic and Radical Processes. A Model for Factor F-430

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Nickel(I)octaethylisobacteriochlorin anion (Ni(I)OEiBC - ) reacts extremely rapidly with aliphatic halides and methyl tosylate in homogeneous DMF solution.The reactivity sequence, CH3 > primary > secondary tertiary, and the rate law accord with an S N 2-like process for the carbon-halogen bond scission.However, the main products of the reactions derive from free radicals.The rate for methyl chloride is 2000 times faster than the corresponding reaction with the super nucleophile Co(I)B12 s -1 and the rate constant for isopropyl bromide is 350 times greater than that observed with CpFe(CO)2 - .The results indicate NiOEiBC - is the fastest nucleophile on record.Studies of the influence of solvent and reactant deuteration and the influence of anion and radical scavengers upon the product distribution suggest the intermediacy of at least one and possibly two nickel alkyls of fleeting lifetime.A novel explanation for the unusual speed of these reactions is put forward.It entails the...
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