Di-r-butyl dicarbonate

Miscellaneous reactions Allyl chloroformate, 9 1,1 -Carbonyldiimidazole, 66 Di-r-butyl dicarbonate, 94 Di- n-carbonylhexacarbonyldicobalt, 99 Palladium(II) acetate-Triphenylphos-phine, 233... 

Di-r-butyl dicarbonate, (CH COCOjCOjCTCI. Mol. wt. 209.17, m.p. 21-22°. Preparation.1 The reagent is prepared as shown from di-r-butyl tricarbonate. 

Related Reagents. 7V-(r-Butoxycarbonyloxy)phthalimide N-(r-Butoxycarbonyloxy)succinimide t-Butyl Azidoformate t-Butyl Chloroformate Di-r-butyl Dicarbonate. 

The potassium compound 19 is readily transformed into 20 (R = alkyl) by the action of alkyl halides. The products are converted into salts of alkylamines RNH2 by acidic hydrolysis50. Uses of di-t-butyl imidodicarboxylate (21) have been reviewed46. Treatment of formamide with di-t-butyl dicarbonate 22 gives the unstable formyl compound 23, which yields 21 by the action of 2-diethylaminoethylamine (equation 18)51. 

In 1996, the tetraphenyl syn-bimane 1 (R = Ph) was obtained in 19% yield when the sodium salt of the 1,3,4-oxadiazinone 2 was treated with di-t-butyl dicarbonate in THF in an attempt to form the 3-Boc derivative. A mechanism was suggested for the conversion of 2 into syn-1 (R = Ph) which involved - ultimately - an intermediate of similar type to that which had been suggested previously for the transformation of 4-chloropyrazolin-5-ones into 1. 

RN — RNHBoc.2 Vicinal azido alcohols are converted directly into v/c-N-r-butoxycarbonylamino alcohols by Pd/C-catalyzed hydrogenation in the presence of di-f-butyl dicarbonate in ethyl acetate at 25°. Yields are 71-93%. 

AMINO GROUP Boron trifluoride ether-ale. l-r-Bulyloxycarbonyltriazole-1,2,4, Di-t-butyl dicarbonate. 4-Dimethylamino-1-t-butyloxycarbonyl pyridinium chloride. CARBONYL GROUP Ceric ammonium nitrate. 1,2-Dihydroxy-3-bromopropane. Sodium N-chloro-p-toluenesulfonamide. Thallium(lll) nitrate. Trichloroethanol. Trimcthylsilyl cyanide. Chloromethyl methyl sulfide. N,N -Diisopropylhydra-zinc. Trichloroethanol. 

Boc-protection To the resulting polymer, di-tert-butyl dicarbonate (5.0 equiv., 0.2 M) in CH2CI2 and EtsN (5.0 equiv, 0.14 mb, 1.0 mmol) were added, and the mixture was stirred for 5 h at r. t The polymer was filtered and washed with water, THF, and CH2CI2, and then dried in vacuo. 

Chiral intermediates for the synthesis of (-)-anisomycin (1) and (+)-anisomycin (anti-1) (153), (R)-2-(p-methoxyphenyl)methyl-2,5-dihydro-pyrrole (142) and its (S)-isomer (+)-187, have been efficiently synthesized from D-tyrosine and L-tyrosine, respectively (Scheme 20) [28]. D-tyrosine was converted to 0-methyl D-tyrosine methyl ester (182) [72-75] which was treated with di-tert-butyl dicarbonate to protect the amino group. Subsequent reduction of the ester group with sodium borohydride in the presence of lithium chloride furnished the alcohol 183. Swern oxidation of 183 followed by chain extension with the anion derived from bis(2,2,2-trifluoroethyl)(ethoxycarbonylmethyl)-phosphonate afforded (Z)-Q ,/0-unsaturated ester (184), which was used immediately without purification to avoid or minimize any possible racemization of the chiral center. Reduction of the ester group of 184 with diisobutylaluminium hydride afforded the alcohol 185 which after mesylation followed by intramolecular cyclization gave the desired 2,5-dihydropyrrole derivative 186. Removal of the tert-butyloxycarbonyl group was achieved by treatment with trifuoroacetic acid to give (-)-142 in 62% overall yield from 182. The (S)-2,5-dihydropyrrole (-l-)-187 was also prepared in the same manner starting from L-tyrosine. Since (-l-)-187 had been transformed into (-l-)-anisomycin (anti-1) (153), (-)-142 could also be transformed to the (-)-anisomycin (1) [26,66]. 

The direct high-pressure amination of ethylene with ammonia to give ethylamine occurs in the presence of acidic zeolite catalysts such as H-elinoptilolite, H-erionite or H-offretite. Primary amines R NH2(R = Bu, cyclohexyl, PhCH2, Ph or Ar) have been monoalkylated by reaction with di-t-butyl dicarbonate, followed by successive treatment of... 

A suspension of Pd-C in ethyl acetate vigorously stirred under H2 until uptake of gas ceased, a soln. of /r 5-2-azidocyclohexanol and di- ert-butyl dicarbonate in the same solvent added, and the mixture stirred at room temp, under H2 for 19 h - product. Y 71%. Pre-saturation of the catalyst is important to prevent nitrile formation. F.e. incl. N-protected a-amino-p-hydroxycarboxylic acid esters and 2-acoxyamines, s. S. Saito et al.. Tetrahedron Letters 30, 837-8 (1989). 

Related Reagents. Allyl Chloroformate Benzyl Chlo-roformate 4-Bromobenzyl Chloroformate t-Butyl Azidoformate l-(t-Butoxycarbonyl)-lEf-benzotriazole 3-A-oxide 1 -(r-Butoxycarbonyl)imidazole 2-(t-Butoxycarbonyloxyimino)-2-phenylacetonitrile A-(t-Butoxycarbonyloxy)phthalimide A-(t-Butoxycarbonyloxy)succinimide V-(r-Butoxycarbonyl)-1,2,4-triazole Di-t-butyl Dicarbonate Ethyl Chloroformate 9-Fluorenylmethyl Chloroformate Isobutyl Chloroformate Methyl Chloroformate 2,2,2-Tribromoethyl Chloroformate 2,2,2-Trichloroethyl Chloroformate 2,2,2-Trichloro-t-butoxycarbonyl Chloride 2-(Trimethylsilyl)ethyl Chloroformate Vinyl Chloroformate. 

Dibutyldibenzo-18-crown-6, see D-00236 Di-rer -butyldibenzo-30-crown-10, see B-00331 Di- r butyldibenzo-33-crown-l 1, see B-00332 Di- er/-butyl dicarbonate, in D-00243 Dibutyl diethylphosphoramidate, in D-00353... 

PBOCST is readily synthesized from the polymerization of r-hutoxycarhonyl oxystyrene via radical or cationic polymerization in liquid sulfur dioxide or alternatively by reacting poly(hydroxystyrene) with di-tert-h xty dicarbonate in the presence of a base PBOCST polymers with narrow dispersity have been prepared by living anionic polymerization of 5-tert-butyl(dimethyl)silyloxystyr-ene), followed by desilylation with HCl to form PHOST and protection with di-tert-butyl carbonate PBOCST is very transparent around the 250-nm region of the spectrum (absorbance <0.1/ p,m), thus making it an ideal candidate for DUV 248-nm lithography. 

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