The Synthetic Routes of 2-ETHOXY-5-(TRIBUTYLSTANNYL)PYRIMIDINE

2-Ethoxy-5-(tributylstannyl)pyrimidine is an important synthetic intermediate in the chemical industry.
It is widely used in the production of various pharmaceuticals, pigments, and other chemical products.
The synthetic routes of 2-ethoxy-5-(tributylstannyl)pyrimidine can be classified into three main categories: indirect, direct, and enantioselective synthesis.

Indirect Synthesis
The indirect synthesis of 2-ethoxy-5-(tributylstannyl)pyrimidine involves the synthesis of 2-ethoxy-5-(tributylstanny)benzaldehyde, which is then converted into the desired pyrimidine.
The synthesis of 2-ethoxy-5-(tributylstanny)benzaldehyde can be achieved through several different routes, including the Williams-McKie reaction or the Corey-Fuchs reaction.
Once the benzaldehyde is synthesized, it can be reduced to the corresponding alcohol using reducing agents such as lithium aluminum hydride or hydrogen in the presence of a suitable catalyst.
The alcohol can then be converted into the pyrimidine using known pyrimidine synthesis methods, such as the Williamson synthesis or the Böckeler synthesis.
The advantage of this route is that it provides a convenient starting material for the synthesis of 2-ethoxy-5-(tributylstanny)pyrimidine.

Direct Synthesis
The direct synthesis of 2-ethoxy-5-(tributylstannyl)pyrimidine involves the condensation of 2-ethoxy-5-bromopyrimidine with tributyl tin chloride in the presence of a Lewis acid catalyst, such as aluminum chloride.
The reaction proceeds through a free-radical mechanism and the desired product can be isolated by Siberian-Breslow oxidation of the bromide to the corresponding nitrile, followed by reduction with lithium aluminum hydride.
The advantage of this route is that it provides a pure product with high yield, and eliminates the need for further purification.

Enantioselective Synthesis
Enantioselective synthesis of 2-ethoxy-5-(tributylstannyl)pyrimidine involves the use of chiral auxiliary or optical resolution techniques to obtain the desired enantiomer.
One such method involves the use of quinine hydrochloride as a chiral auxiliary to force the desired stereochemistry during the synthesis.
Another method involves the use of asymmetric oxidation or reduction steps to obtain the desired enantiomer.
The advantage of this route is that it provides a highly enantioenriched product, which can be useful in pharmaceutical and agrochemical applications where enantiomeric purity is important.

In conclusion, the synthetic routes of 2-ethoxy-5-(tributylstannyl)pyrimidine are diverse and can be customized to suit the specific needs of the synthetic process.
The indirect and direct syntheses provide convenient and efficient methods for the synthesis of the desired product, while the enantioselective synthesis provides a highly enantioenriched product for use in specific applications.