6533b829fe1ef96bd12897bb

RESEARCH PRODUCT

Eight-membered Rings with Two Heteroatoms 1,5

subject

description

The chapter of the third edition of Comprehensive Heterocyclic Chemistry (CHEC III) 12.24 titled ‘Eight-membered Rings with two Heteroatoms 1,5’ deals with diheterocines rings with two heteroatoms in a 1,5 relationship, namely 1,5-diazocine, 1,5-oxazocine, 1,5-thiazocine, 1,5-dioxocin, 1,5-oxathiocin, and 1,5-dithiocin. This chapter covers the literature from 1996 to 2006 and also reports those articles published in 1995 which were not reported in CHEC-II(1996). In this edition, in addition to the uncondensed derivatives, eight-membered 1,5-heterocycles fused to five-, six-, and seven-membered carbocycles or heterocycles are covered. Bridged diheterocines, which actually constitute the majority of the compounds reported were covered as well. The main change in this chapter, with respect to CHEC-II(1996), is related to the ‘Theoretical Methods’ section. Such a section in CHEC-II(1996) was a unique section, placed immediately after the introduction and dealt with all the classes of eight-membered heterocycles with two heteroatoms. In this edition, each section dealing with a single class of heterocycles has its own ‘theoretical methods’ section. The ‘Experimental Structural Methods’ section has received a strong impulse since, with some exceptions, the great majority of the reported derivatives have been adequately characterized. As already done in CHEC-II(1996), all six systems are discussed separately with each discussion following the same general format. In case particular sections are not mentioned, it means that no chemistry has been reported.