Ferf-Butoxy

Tris(ferf-butoxy)siloxide molecular precursors of V(IV) and V(V) can be prepared via simple silanolysis reactions. For example, OV[OSi(O Bu)3]3 was obtained in 85% yield by reaction of OVCI3 with excess HOSi(O Bu)3 in the presence of pyridine [79]. Although crystals of sufficient quality for an X-ray structural analysis of 0V[0Si(0 Bu)3]3 were not obtained, its identity was confirmed by various spectroscopic and analytical techniques. Additionally, ( BuO)3VOSi(O Bu)3 and ( BuO)2V[OSi(O Bu)3]2 were obtained via reaction of V(0 Bu)4 with 1 and 2 equiv of HOSi(O Bu)3, respectively, in toluene at 80 °C [80] (Eq. 5). Both (fBu0)3V0Si(0 Bu)3 and CBu0)2V[0Si(0 Bu)3]2 are monomeric in the solid state, and possess only monodentate siloxide ligands... 

The only group 8 tris(ferf-butoxy)siloxide molecular precursor that has been reported thus far is the iron(III) complex Fe[OSi(O Bu)3]3 THE, synthesized via the reaction of FeCls with NaOSi(0 Bu)3 in THF (74%) [71,97] (Eq. 6). An... 

The zinc tris(ferf-butoxy)siloxide complex Zn[0Si(0 Bu)3]2 2 was prepared from the reaction of ZnMe2 with HOSi(O Bu)3 [107]. This complex was structurally characterized as an asymmetric dimer with four - OSi(O Bu)3 ligands, each exhibiting a unique coordination mode ( fi - , r] ... 

For the photolysis of ferf-butyl nitrite a possible reaction mechanism (Scheme 6) consists of the production of ferf-butoxy radicals (equation 3), followed by their decomposition to give acetone and methyl radicals (equation 4). The latter are trapped by the nitric oxide liberated in the first step (equation 5). However, the absence of ethane production in the actual experiments suggested that an intramolecular formation of nitrosomethane is unlikely ". ... 

Diethyl (i S)-2-[(4.S)-3-(ferf-Butoxy carbonyl )-2,2-dimethyloxazolidin-4-yll-1,1-difluoroethylphos-... 

Oral progestational activity is retained when the ketone at the 3 position is reduced to an alcohol. Treatment of ethindrone (13-6) with the bulky reducing agent lithium aluminum-tri-ferf-butoxy hydride leads to attack from the more open a face and the formation of the 3 3 hydroxy derivative (14-1). Acylation under forcing conditions affords the 3,17-diacetate derivative, ethynodiol diacetate (14-2) [17]. 

II ferf-Butoxy-l-chloromethylsulfonyl)-4 methylbenzene, 57, 100 sec-Butyl alcohol, 58, 78 ferf-Butyl alcohol, 58, 78 ferf-Butyl alcohol, potassium salt, 56, 29 rerf-Butylamine, 55, 96 1 Butvl-2-chlorobenzene 58, 133... 

The energy of activation for the addition of trifluoroinethyl radical to the C=0 double bond of hexafluoroaeetone was calculated to be 9.7 0.26 kcal. mol.-1 and that for the decomposition of the perfluoro tert-butoxy radical was found to be 30.6 1.3 kcal. mol.-1, so that AH for the formation of the perfluoro ferf-butoxy radical is —20.9 kcal. mol.-1. Thus at high light intensities and elevated temperatures, the contributions of these reactions cannot be neglected. 

Methyl l-[(2S)-3-ferf-Butoxy-2-(tert-butoxycarbonylaniino)-3-oxopropyl]cydopropanecarboxylate... 

Ethyl JV- [2-Amino-6-(benzyloxycarbonylaniino)purin-9(9/7)-yl]acetyl)-V-[2-(ferf-butoxy-carbonylamino)ethyl]glycinate (15) 1361... 

Esters, amides, and primary alcohols are obtained from benzo[6]-thiophene carboxylic acids by standard procedures.337 481,585 692 093,695 Acid chlorides undergo the Arndt-Eistert reaction,337,568,689 react with diethyl ethoxymagnesium malonate to give the corresponding methyl ketone,144 557 and are reduced to the aldehyde with 1 ithium tri-ferf-butoxy aluminohydride.33 7... 

Wu JQ, Beranek I, Fischer H (1995) Absolute rate constants for the addition of cyanomethyl (CH2CN) and (ferf-butoxy)carbonylmethyl (CH2C02C(CH3)3) radicals to alkenes in solution. Helv Chim Acta 78 194-214... 

Paul H, Small RD, Scaiano JC (1978) Hydrogen abstraction by ferf-butoxy radicals. A laser photolysis and electron spin resonance study. J Am Chem Soc 100 4520-4527... 

Scheme 10.14 /3-Scission of the ferf-butoxy radical for the measurement of the relative rates of hydrogen...

The first-order ft-scission of the ferf-butoxy radical is one of the oldest radical clock reactions and has been used for over 50 years for the measurement of the relative rates of hydrogen abstraction from organic compounds (AH) in solution (Scheme 10.14). At low conversions, when the concentration of AH has not appreciably changed, the ratio of the rate constants for hydrogen atom abstraction, kAH> and /3-scission, kp, can be determined simply by analysis for acetone and ferf-butyl alcohol formation in the reaction. This is most conveniently achieved by gas chromatography ... 

Experimental support for the given order of stability in the fluoromethyl series has been provided in a study by Jiang et al. of the radical fragmentation of the respective series of fluorinated ferf-butoxy radicals [32] ... 

Example of a protected amine. The protected amino acid V -ferf-butoxy carbonyl (Boc)-l-lysine, when used as the amine to synthesize the triazine-based ligands, is deprotected prior to screening with protein. Protected immobilized ligands, after washing with the appropriate solvent in a sintered funnel, are immersed in 99% v/v trifluoroacetic acid (TFA) and stirred for 1 h in the fume hood. Methanol is added to dilute the TFA, and the waste solution is carefully disposed of. The matrixes are washed sequentially with methanol and distilled water (3 10 gel... 

Crotylmetallation of-y-heterosubstituted vinyl lithium derivatives preparation of (3/ , 4S, 5S )-3,4-dimethyl-5-ferf-butoxy-oct-1-ene... 

Z)-iodo-3-(ferf-butoxy)hex-1-ene28 (FW 282), 500 mg, 1.77 mmol irritant... 

Structural evidence of the formation of alkylated siloxide complexes was obtained from the reaction of homoleptic tetramethylaluminates Ln(AlMe4)3 with one equivalent of tris(ferf.butoxy)silanol HOSi(Of-Bu)3. This fast protonolysis reaction results in heterobimetallic Ln/Al complexes Ln[OSi(Of-Bu)3](AlMe4)2(AlMe3) (Ln = Y, Ce, Pr, Nd, La) via quantitative... 

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