Glance Index to Typical Phthalazine Derivatives Available by Primary Syntheses

GLANCE INDEX TO TYPICAL PHTHALAZINE DERIVATIVES AVAILABLE BY PRIMARY SYNTHESES 

This glance index may assist in the choice of a primary synthesis for a required phthalazine derivative such syntheses are based on aliphatic, carbocyclic, or heterocyclic substrates with or without ancillary synthons. It should be remembered that products analogous to those formulated may often be obtained by quite minor changes to the substrate and/or synthon involved. Products arising from syntheses that appear to be of little preparative value are omitted from this index. 

Since the publication of Simpson s volume and Patel s update in this series, several reviews of phthalazine chemistry have appeared,among which that of Stanovnik ° is particularly useful. 

Because phthalazine is reasonably inexpensive to purchase, there has been little incentive to develop new or improved synthetic procedures. However, a convenient primary synthesis has been reported (see Section 8.2.2.4) 1,4-dihydrazinophthala-zine (1) has been oxidized to phthalazine (2) (NaOH, EtOH, H2O, 02i, 20°C, 3-4 h and phthalazine may be recovered from its 2-methiodide by treatment with neat refluxing pyridine hydrochloride.  

Cinnolines and Phthalazines Supplement II, The Chemistry of Heterocyclic Compounds, Volume 64, by D.J. Brown Copyright 2005 John Wiley Sons, Inc. 

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