BIS 2,2,2-TRICHLOROETHYL AZODICARBOXYLATE

Silylated primary allylic amines, e.g. CH2=CHCH2N(SiMe3)2, are produced from allylic chlorides and the mixed reagent AgI/LiN(SiMe3)2205. The formation of allylic amines from olefins by the ene reaction is shown in equation 77. The ene adducts 205 from bis(2,2,2-trichloroethyl) azodicarboxylate are converted into 206 by zinc dust in acetone/acetic acid206. 

B. Bis(2,2,2-trichloroethyl) azodicarboxylate Caution Large amounts of nitrogen oxides are evolved during the oxidation with fuming nitric acid. Therefore, operations should be conducted in an efficient fume hood. 

Bis(2,2,2-trichloroethyl) azodicarboxylate has been prepared by oxidation of bis(2,2,2-trichloroethyl) hydrazodicarboxylate with dinitrogen tetroxide.3... 

BIS(2,2,2-TRICHLOROETHYL) AZODICARBOXYLATE [Diazenedicarboxylic acid, bis(2,2,2-trichloroethyl) ester]... 

The synthesis of BENZYL ISOCYANIDE from benzaldehyde via reductive amination with 5-aminotetrazole followed by oxidation of the resultant amine with sodium hypobromite provides a general method for the synthesis of isocyanides. The preparation of BIS(2,2,2-TRICHLOROETHYL) AZODICARBOXYLATE makes available an alternative to dimethyl azodicarboxylate that is not only more reactive in Diels-Alder reactions but whose ester groups can be removed under neutral conditions. 

A. 1 -(2-Acetyl-4,6-dimethoxyphenyl)-1,2-hydra2inedicarboxy ic acid bis(2,2,2-trichloroethyl) ester. A 2-L, round-bottomed flask, equipped with a magnetic stirrer, thermometer, and an ice bath is charged with 3,5-dimethoxyacetophenone (20.00 g, 111.0 mmol) (Note 1) and dichloromethane (CH2CI2, 555 mL) (Note 1). At 0-5°C, under nitrogen, trifluoromethanesultonic acid (980 pL, 11.1 mmol) (Note 1) is added in one portion. To the resulting yellow solution, bis(2,2,2-trichloroethyl) azodicarboxylate... 

Bis(2,2,2-trichloroethyl) azodicarboxylate was purchased from Aldrich Chemical Company, Inc. It can also be prepared as described in reference 2. 

Acetyl-4,6-dimethoxyphenyl)-l, 2-hydrazinedicarboxylic acid bis(2,2,2-trichloroethyl) ester 1,2-Hydrazinedicarboxyiic acid, l-(2-acetyl-4,6-dimethoxyphenyl)-, bis(2,2,2-lrichloroethy ) ester (13) (154876-13-8) Trifluoromethanesulfonic acid Methanesulfonic acid, trifluoro- (8,9) (1493-13-6) Bis(2,2,2-trichloroethyl) azodicarboxylate Diazenedicarboxylic acid, bis(2,2,2-trichloroethyl) ester (9) (38857-88-4)... 

We know of no instances of explosions with t-butyl azodicarboxylate [Org. Synth., Coll. Vol. V. 1973, 1601 or bis(2,2,2-trichloroethyl) azodicarboxylate [Org. Synth., Coll. Vol. VI11990, 56], which would be expected to be less prone to explosion than the methyl or ethyl azodicarboxylates because of their higher molecular weights. Nevertheless, for safety they too should be prepared and handled behind good shielding and, if they are to be kept for a long time, stored in a shock-stable solvent as described above. 

DIELS-ALDER DIENOPHILES Bis(2,2,2-trichloroethyl) azodicarboxylate. 1-Bromo-2-chlorocyclopropene. Chromium carbene complexes. (R)-Ethyl p-tolysulfinyl-methylenepropionate.l (S)-a-Hydroxy-p,p-dimethylpropyl vinyl iketone. (IR)-m-3-Hydroxy isobomyl ndopentyl ether. Oxa-zolidones, chiral. Phdnylselenenyl ben-zenesulfonate. 

The [4+2] cycloaddition reaction of furanoid and pyranoid glycals with azodicarboxylates allows the introduction of a nitrogen atom at C-2 of a carbohydrate, and the adducts thus obtained can be converted to structurally complex 2-amino saccharides under mild conditions. Towards this end, dibenzyl and bis(2,2,2-trichloroethyl) azodicarboxylates were used as dienes since they allow the free amines to be generated in a single operation under mild conditions later in the synthetic sequence. 

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