Vapochromic platinum-complexes and salts

摘要

The present invention relates to a process for indicating the presence of organic vapors comprising the steps of determining the color, absorption or emission spectra of a Pt--Pt double-complex salt of platinum or a neutral platinum complex in the absence of organic vapor, exposing said double-complex salt of platinum or a neutral platinum complex to a gaseous environment, determining the color, absorption or emission spectra of said double-complex salt of platinum or a neutral platinum complex after exposure to said gaseous environment, and comparing the color, absorption and/or emission spectra of said double- complex salt of platinum or a neutral platinum complex in the absence of organic vapor with the color, absorption and/or emission spectra of said double-complex salt of platinum or a neutral platinum complex after exposure to said gaseous environment to determine if there is a difference in the color, absorption and/or emission spectra. The double- complex salt is represented by the general formulas [Pt(CN--C.sub.6 H. sub.4 -alkyl group).sub.4 ][PtX.sub.4 ] or [Pt(phen)(CN--C.sub.6 H.sub.4 - alkyl group).sub.2 ][PtX.sub.4 ] of [Pt(bpy)(CN--C.sub.6 H.sub.4 -alkyl group).sub.2 ][PtX.sub.4 ] and more preferably by the formulas [Pt(CN--C. sub.6 H.sub.4 --C.sub.n H.sub.2n+1).sub.4 ][Pt(CN).sub.4 ] or [Pt(phen) (CN--C.sub.6 H.sub.4 -alkyl group).sub.2 ][Pt(CN).sub.4 ] of [Pt(bpy)(CN-- C.sub.6 H.sub.4 -alkyl group).sub.2 ][Pt(CN).sub.4 ], wherein n is a whole positive integer between 1 and 100. Still more preferably n is between 1 and 20. phen is 1,10-phenanthroline or an alkyl substituted phenanthroline, bpy is 2,2'-bipyridine or an alkyl substituted bipyridine. Other bidentate or tridentate amine ligands are also possible. The PtX. sub.4.sup.2- group can also be Pt(NO.sub.2).sub.4. sup.2-, Pt(Cl).sub.4. sup.2-, Pt(Br).sub.4.sup.2-, Pt(NCO).sub.4.sup.2-, Pt(NCS).sub.4.sup.2- or Pt(oxalate).sub.2.sup.2-. For the bpy and phen complexes, the palladium analogs of PtX.sub.4.sup.2- (ie. PdX.sub.4.sup. 2- are also possible). The neutral complexes are represented by the general formulas Pt(CN--C.sub.6 H.sub.4 -alkyl group).sub.2 X.sub.2, and Pt(CN--C.sub.6 H. sub.4 -alkyl group)(C(Y)═NH--C.sub.6 H.sub.4 -alkyl group)X.sub.2 wherein n is a whole positive integer between 1 and 100 and Y can be O- alkyl, NH-alkyl or N(alkyl).sub.2. Still more preferably n is between 1 and 20. The alkyl substituents may be different within the same complex. X is preferably CN.sup.-, but any other negatively charged groups such as NO.sub.2.sup.-, NCO.sup.-, NCS.sup.-, Cl.sup.-, Br.sup.-, I.sup.-, oxalate, etc. may also be used. The two X.sup.- groups are not necessarily the same.