Cleavage general procedure

Cleavage of allyl carboxylates (general procedure) f To a solution of NaHTe (prepared in situ from tellurium powder (1.30 g, 1.0 mmol) and NaBH4 (0.90 g, 2.4 mmol) in EtOH (20 mL) buffered with deoxygenated HOAc (1.2 mL in 5 mL EtOH)) is added the allyl carboxylate (0.005 mol). The mixture is refluxed under N2 for 2 h, then filtered, the filtrate... 

Cleavage of trichloro-t-butylcarbamates (general procedure) A 1% solution of the trichloro-t-butylcarbamate derivative and 24 mol% of bis(2-thienyl) diteUuride in THF is heated to 60°C under Nj. A 1% aqueous solution of NaBH4 (stabilized with three drops of a 10% NaOH solution) is added dropwise until the red colour of the catalyst disappears. This usually requires 4 or 5 equiv of NaBH4 and is carried out over a period of 30 min. The volatile components are removed in vacuo. The mixture is then poured into HjO and extracted with ether. The amines are isolated by flash chromatography or by acid extraction. 

A general procedure for the iodine reaction in the solid phase is shown in Scheme 9. Both Boc and Fmoc chemistry can be used to assemble the linear S-protected bis-cysteine peptides and for thiol protection the well-established Acm and Trt groups are usually used. Suitable solvents for the thiol-deprotection/oxidation step by iodine to form the disulfide are CH2C12, DMF, or aqueous AcOH. The final deblocking and cleavage from the resin is carried out under standard conditions. Modification at sensitive amino acid residues caused... 

Alkylated Carbonyl Compounds and Recovery of the Chiral Auxiliary by Cleavage of Alkylated SAMP/ RAMP-Hydraznnes General Procedure for Ozonolysis3 ... 

Alkylated Carbonyl Compounds by Cleavage of Alkylated SAMP/RAMP-Hydrazoncs General Procedure for Acidic Hydrolysis of Methoiodides ( Salt Method )3 ... 

Alkylated Ketones by Cleavage of Alkylated SAMP-Hydrazones General Procedure for Oxidation with Magnesium Monoperoxyphthalate Hexahydrate2 ... 

Solutions of these metals in liquid ammonia effect (i) the reduction of a range of functional groups such as carbonyl and acetylenic and also conjugated and aromatic systems, and (ii) cleavage of benzyl and allyl ethers and thioethers. These reactions are usually carried out by the general procedure of adding the metal to a solution of the substrate in liquid ammonia to which dry methanol or ethanol or t-butanol has been added to provide a ready proton source (alcohols are more acidic than ammonia).34... 

General Procedure for Cleavage of Phenols Using the Suzuki Coupling Reaction Preparation of Resins 15-17 and Compounds 18... 

General Procedure for Cleavage of Phenols by a Reductive Elimination Reaction Preparation of Compounds 20 and 22... 

Cleavage of the THP-Protected Purines 6 and 7 General Procedure. A mixture of a THP-protected base 6 or 7 (0.6—0.8 mmol), Dowex 50x8 (H+) (ca. 300 mg), methanol (10 mL) and water (1 mL) was refluxed for 1 h, then filtered while hot and the resin was washed with saturated methanolic ammonia (5 mL) followed by methanol (20 mL). The combined filtrates were evaporated and the residue was codistilled with toluene. Crystallization of the residue from methanol/toluene with an addition of heptane afforded the free bases 10 or 11. 

Aliphatic diamines are made by reduction of amino oximes by these same general procedures. Sometimes catalytic hydrogenation gives low-boiling cleavage products. ... 

Pd(0)-Catalyzed Aloe Cleavage with PhSiHj General Procedure ... 

Allyl Ester Cleavage Using Chlorotris(triphenylphoshine)rhodium(I) General Procedure I ... 

Acidolytic Deprotection and Cleavage from Peptidyl Resin of Cys(Trt)-Containing Peptides under High TFA Conditions General Procedure P 4... 

Cleavage of Peptides from Fluorenylmethyl-Based Resins General Procedure P ... 

Cleavage of N-carbohenzoxy derivatives. In a general procedure for selective cleavage, the N-carbobenzoxy amino acid or peptide is treated with excess reagent... 

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