By Carey F., Sundberg R.
Read Online or Download Advanced Organic Chemistry. Structure and Mechanisms PDF
Similar organic chemistry books
HardPress vintage Books sequence
During this quantity, these practical teams containing heteroatoms that experience won value in natural synthesis are handled intimately. The creation of those numerous teams and their proper changes are defined and some of the facets of chemoselectivity, regioselectivity and stereoselectivity are mentioned.
Additional resources for Advanced Organic Chemistry. Structure and Mechanisms
E. Bergbreiter and M. Momongan, in Comprehensive Organic Synthesis, ed. B. M. Trost and I. Fleming, vol. 2 (Oxford: Pergamon Press, 1991), p. 503. 20 Formation of carbon–carbon single bonds or nitriles. High yields of monoalkylated carbonyl compounds can be obtained. The first examples of this chemistry were reported by Michael as early as 1887, and hence this type of reaction is often termed a Michael reaction. 30 During conjugate addition, the carbanion adds to the ␤-carbon of the ␣,␤-unsaturated carbonyl compound.
Am. Chem. , 103 (1981), 3099. Y. Tanabe, N. Matsumoto, T. Higashi, T. Misaki, T. Itoh, M. Yamamoto, K. Mitarai and Y. Nishii, Tetrahedron, 58 (2002), 8269. 1 Main-group chemistry 35 atom. 1]non-9-yl triflate (9-BBNOTf). 68) Me syn : anti 9-BBNOTf O nPrCHO Bu2BOTf B 10 : 90 OH O nPrCHO Me SPh SPh Me Me syn : anti 97 : 3 The situation becomes a little more complex if the aldehyde contains a chiral centre, as in 2-phenylpropanal. 69). The relative stereochemistry of the substituents at C-2 and C-3 is controlled by the geometry of the enolate.
Shih, J. Am. Chem. , 103 (1981), 2127. 42 Formation of carbon–carbon single bonds aldehyde that has been pre-complexed to a Lewis acid such as diethylaluminium chloride. In such cases one of the two anti stereoisomers predominates in the aldol addition reaction. This is thought to be a consequence of an open (acyclic) transition state, rather than the normal chair-like six-membered cyclic transition state. 81). 81) Ph ratio of major (anti) to other stereoisomers 32 : 1 An alternative approach to the asymmetric aldol reaction involves the use of a chiral ligand attached to the metal atom of the enolate species.
Advanced Organic Chemistry. Structure and Mechanisms by Carey F., Sundberg R.