Carved synthesis

Though the pertinent experiment in the corrin series has not yet been reported, a record of the analogous experiment in the porphyrin series has appeared [84], In contrast to corrins, in haems all four acetate side chains of the parent urogen III have been decarboxylated to methyl groups. In principle, these could be carved out as acetic acid and analysed for chirality if the starting succinate had been stereospecifically labelled with deuterium as well as with tritium. The synthesis of (2/ )-[2-2H,2-3 H]succinic acid was achieved by incubating (37 ,S)-[3-3 H]-... 

The synthesis of Cp 3U Cp = p -CsMes carved a new path for the researchers to go one step ahead in the electrochemical studies of organoac-tinide complexes. The reduction reaction involving more than two electrons are not common for metal complexes containing just one metal. However, the synthesis of complexes of the type Cp 3M led to the development of sterically induced reduction (SIR) chemistry in which sterically crowded complexes of redox inactive metals act as reductants [87,88]. Evans et al. showed that the sterically induced reduction couple, U(III)/U(IV), can act as a multielectron reductant [89]. As an example, Cp 3U reacts as a three-electron reductant with 1,3,5,7-C8H8, (Eq. 12) in which one electron arises from U(III) (Eq. 13) and two result from two CsMes /CsMes half reactions (Eq. 14) presumably via SIR. This phenomenon was further corroborated by the stepwise reduction of phenyl halide with Cp 3lJ (Eq. 15) ... 

Quantum dots provide a great example of the enabling role that chemistry plays in the synthesis of nanomaterials. In that case, we harness the solubility rules to generate our nanomaterials. A simplified precipitation reaction for the synthesis of CdSe is shown in Figure 14.4. This type of nanoscale synthesis is often referred to as bottom-up because it starts with molecular or atomic building blocks. The other main approach to synthesize nanomaterials is called top-down, in which we carve out a nanostructure from something larger. An example of this is found in the electrochemical synthesis of porous silicon nanostructures from crystalline silicon wafers. 

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