Selective cleavage amines

Species 5 (Scheme 8), commonly known as dialkylaminodifluorophosphines, are readily synthesized via the selective cleavage of the phosphorus-carbon bond of difluoro(trichloromethylphosphane) by the action of secondary amines [65,66]. Compounds 5 show selective F/H exchange with LiAlH4/HN(Tr)2 to give the respective PH2 (P-unsubstituted) phosphinous amides [13]. 

The electrochemical behaviour of silyl-substituted nitrogen compounds is also interesting. The introduction of a silyl group at the carbon adjacent to the nitrogen of carbamates causes a significant decrease in the oxidation potentials, although such effect is much smaller for amines. Preparative electrochemical oxidation of silyl-substituted carbamates in methanol results in smooth and selective cleavage of the C Si bond and introduction of methanol at the a-... 

Phosphonamidates are usually prepared by coupling an activated phosphonate monoester with the amine of interest. Since most phosphonate amino add analogues are prepared as their diesters, this procedure first requires selective cleavage to the monoester. Activation from the phosphonic acid oxidation level typically involves preparation of the phosphono-chloridate, but it can also be accomplished by chlorination of an H-phosphinic acid analogue. 

Selective cleavage of 2,3-epoxy esters.1 The highly toxic reagent i -Pr2(C2H5)-NHN3 (l)2, obtained by combination of hydrogen azide and the amine, cleaves 2,3-... 

Iodotrimethylsilane, for selective cleavage of protective groups, 17 (Ref. 15), 157, 180 Isobomyl carbamates, to protect amines, 347 Isobomyl ethers, to protect phenols, 155 S-Isobutoxymethyl monothioacetals, to protect thiols, 290... 

N-Salicylideneamines, to protect amines, 370 Selective cleavage, 411-412 of benzyl carbamates, 339-340 of benzyl ethers, 49-56 of catechol protective groups, 171 of N- vs. 5-dimethylphosphinothioyl groups, 307... 

One of the characteristic features of the metal-bis-acetylide complexes in chemical reactions is that they undergo a ligand exchange reaction with metal dihalides in amines in the presence of a cuprous halide catalyst to produce a monoalkynyl-metal-monohalide complex (Eq. IS) which results from selective cleavage of the metal-carbon bond weakened by the /ram-alkynyl group in the bis-acetylide... 

Furthermore, trifluoroacetic acid anhydride treatment of allylic, propargylic, homopropargylic, and some benzylic tertiary 2,4-dimethoxybenzyl amines 7 leads to highly selective cleavage of their benzylic C —N bonds. The resultant trilluoroacetamides (e,g 8a) can then be readily converted into the corresponding secondary amines. ... 

Amides can in most cases be readily synthesized from activated derivatives of carboxylic acids and amines. They are fairly stable and often need harsh conditions for their removal. On the one hand this prompted a search for advanced methods for their selective cleavage on the other, however, amides generally are used for the protection of chemically stable compounds, e.g. in nucleotide chemistry. In more recent developments, acceleration of the deprotection reaction by intramolecular attack and the advantageous properties of amido hydrolases have been exploited. 

The SmI2-II20 amine system has also been used for the selective cleavage of allyl ether-protected alcohols (Scheme 8.14). This method shown to be useful in the deprotection of alcohols and carbohydrates.16... 

Selective cleavage of a single BOC group from a di-BOC amine... 

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