No abstract

This review updates the original Science of Synthesis chapter (Section 17.9) on phthalocyanines and various ring-fused, ring-contracted, and ring-expanded analogues. It adds some recently published methods, examples, and variations on the synthesis of unsubstituted phthalocyanines and metal phthalocyanines, as well as identically and nonidentically substituted phthalocyanine derivatives. Besides peripheral substitution, axial functionalization is also discussed, but attention is focused only on those methods that represent appreciable progress for a particular type of metal coordination and axial functionalization, provide phthalocyanines with specific features such as chirality, or allow the functionalization of phthalocyanines with entities that are difficult to introduce at the peripheral sites. This account also includes sections on new types of phthalocyanine derivatives and analogues that were not covered in the original chapter, as well as the progress made in the synthesis of some of these families in the decade since 2003.

This chapter is an update to the earlier Science of Synthesis contribution (Section 34.10) describing methods for the synthesis of β-fluoroamines. This topic has continued to attract signficant attention from the synthetic community, largely due to the medicinal importance of this class of compounds. A wide variety of new methods have been developed, and this review focuses on examples that were published between 2005 and 2015.

This chapter is a revision of the earlier Science of Synthesis contribution describing methods for the synthesis of fluoroalkanes by substitution of a halogen atom. It includes additional methods published up until 2016. Newer approaches involve the use of fluoride complex reagents and the use of solvent effects to avoid competitive elimination reactions.

This review presents an overview of the developments in pyrazole synthesis since the beginning of the 21st century. It includes the synthesis of the pyrazole core by ring-closing reactions, ring expansion or contraction, and aromatization. The introduction of substituents onto the pyrazole ring is also covered. Novel synthetic methods that have been developed since the original Science of Synthesis review on pyrazoles (Section 12.1) include various multicomponent approaches in which multiple bonds are formed, cross coupling, and C—H activation reactions of pyrazole derivatives.