Condensation of 2,3-pyridinediamines with acetonylacetone

Abstract

<span style="font-size:12.0pt;font-family: " times="" new="" roman";mso-fareast-font-family:"times="" roman";mso-ansi-language:="" en-in;mso-fareast-language:en-in;mso-bidi-language:ar-sa"="" lang="EN-IN">The reaction of 2,3 -pyridinediamine <b style="mso-bidi-font-weight:normal">1a</b> and its 5-bromo analogue <b style="mso-bidi-font-weight:normal">1b</b>, independently, with acetonylacetone leads to the formation of 1:1 condensation products irrespective of the molar ratios employed. The condensation products <span style="font-size:12.0pt;font-family:" times="" new="" roman";mso-fareast-font-family:="" hiddenhorzocr;mso-ansi-language:en-in;mso-fareast-language:en-in;mso-bidi-language:="" ar-sa"="" lang="EN-IN">have <span style="font-size:12.0pt;font-family:" times="" new="" roman";="" mso-fareast-font-family:"times="" roman";mso-ansi-language:en-in;mso-fareast-language:="" en-in;mso-bidi-language:ar-sa"="" lang="EN-IN">been assigned 2-amino <b style="mso-bidi-font-weight: normal">2a</b> and 5-bromo-2-amino-3(2',5'-dimethylpyrrolyl)pyridine <b style="mso-bidi-font-weight:normal">2b</b> structures. Authentic chemical evidence is given in support of the claim for these structures ruling out the equally probable alternative structure 3 for these compounds. Attempted studies on the reactivity of the latter compounds towards electrophilic reagent such as acetic anhydride, benzoylchloride, and arylsulphonyl chlorides have been described.</span></span></span>