3,399,137 United States Patent Office Patented Aug. 27, 1968 1. 2 3,399,137 chloric acid, carbon monoxide, oxygen, and chemical GENERATION OF LIGHT BY THE REACTION OF energy. It is clear that an essential mechanistic feature ANHYDRDES OF OXALC ACID WITH A PER of the Chandross reaction, as represented by Chandross, OXDE IN THE PRESENCE OF A FLUORESCER is the splitting out of HCl from a six-membered cyclic Michael McKay Rauhut, Norwalk, Conn., and Laszlo transition state. Thus the process as described by Chan Joseph Bollyky, New York, N.Y., assignors to Amer dross requires the specific structure (2) since any alter ican Cyanamid Company, Stamford, Conn., a corpora tion of Maine ation that eliminates the possibility of HCl elimination in No Drawing. Continuation-in-part of application Ser. No. a cyclic transition state would defeat the chemilumines 425,599, Jan. 14, 1965. This application Sept. 8, 1965, cent process. Ser. No. 485,920 10 An extensive investigation which we have carried out 16 Claims. (C. 252-188.3) has shown that, contrary to the teachings of Chandross, certain other oxalic acid compounds when reacted under certain conditions can unexpectedly provide chemilum ABSTRACT OF THE DISCLOSURE inescence. 5 The mechanism of the oxalyl chloride reactions (as A composition for the production of chemiluminescent represented by Chandross) is an entirely different and light, intermediate reactants which when reacted with distinct mechanism from that of this invention disclosed other necessary reactants produce chemiluminescent light, herein, as is discussed at length below. and the chemiluminescent process comprising admixing It should also be recognized that the mechanisms by reactants comprising an oxalic acid type; also, novel 20 which chemiluminescent light may be generated are so chemiluminescent reactant compounds. poorly understood that it is not possible at present to predict those structures which convey the chemilumines cent property. This is amply illustrated by the phthalhy This is a continuation-in part of application Ser. No. drazide series of compounds, some of which are chemi 425,599, filed Jan. 14, 1965, now abandoned. 25 luminescent and some of which are not chemiluminescent The present invention relates to novel compositions of (see A. Bernanose, Bull. Soc. Chim. France, 17,567 matter and reactions and to the direct generation of light (1950)). from chemical energy employing such compositions. By It is an object of this invention to obtain a chemi “light' as referred to herein is meant electromagnetic luminescent composition and a process of employing said radiation at wavelengths falling between 350 mu, and 30 composition whereby a high efficiency may be obtained 800 mu. in the conversion of chemical energy into light. The art of generating light from chemical energy, i.e., Another object is to obtain a chemiluminescent com chemiluminescence, is continually in search of composi pound which produces a light over an extended period of tions which when reacted substantially improve the in time. tensity and lifetime of light emission as contrasted to 35 Another object of this invention is to obtain a chemi known chemiluminescent compositions and reactions. Ob luminescent composition which attains a light of substan viously, improved compositions are constantly in demand tially higher intensity than has been obtained with former for use as signal devices, for area illumination, etc. chemiluminescent compositions. The art has known for some time that oxalyl chloride Another object of this invention is to obtain a chemi in combination with aqueous (30%) hydrogen peroxide 40 luminescent composition which may be employed to ob and a fluorescent compound generates a light whose life tain light by a process which is mechanically simple and time is very short (on the order of about 8 to 30 seconds) which is economically inexpensive. and whose intensity is of little practical utility. Numerous Another object of this invention is to obtain a chemi attempts have been made to improve this chemilumines luminescent reactant which is stable over a long period cent composition and many others similar to it, but with of time and which may be subsequently reacted to ob little success. tain chemiluminescent light. According to a publication by Edward A. Chandross, Another object of this invention is to obtain a chemi (Tetrahedron Letters No. 12," pp. 761–765, 1963) the luminescent reactant which when reacted will obtain chemiluminescent reaction employing oxalyl chloride may chemiluminescent light by a process which is not haz be represented as follows: 50 ardous. Another object of this invention is to obtain a chemi luminescent reactant which when employed in the presence (1) Cl-C-C-Cl + HaOa - of a fluorescent compound will produce chemiluminescent O light. 55 Another object of this invention is to obtain a reaction c. product formed by the reaction of an oxalic acid type 9. (=o -- HCl, followed by - anhydride of the formula described below with a per o Cl oxide, fluorescent compound, and a diluent which may B include water. reaction (2) We have unexpectedly discovered that the objects of (2) 60 this invention are obtained by admixing (1) an oxalic C acid anhydride or an oxalic acid-type anhydride, (2) a peroxide, (3) a fluorescent compound and (4) a diluent. w o If conditions are not acid, water need not be added to O Y ^ Cs the reaction, but the presence of a minor amount of 4.() - HC1 + 2Co+ 0 + chemical energy 65 water is preferred. The di-anhydrides are the preferred N reactants. N The term "chemiluminescent reactant,' as used herein, means a mixture which will result in a chemiluminescent In the above reaction, a cyclic transition structure is first reaction when reacted with other necessary reactants in formed, followed by a breakdown of the ring into hydro 70 the process as disclosed herein. 3,399,137 3 4 The term "chemiluminescent composition,' as used (b) halogen: e.g., chloropyridyl-; herein, means a mixture which will result in chemilu (c) by acyloxy groups: e.g., acetoxypyridyl-; minescence. (d) by carbonyl groups: e.g., formylpyridyl-; The term "admixing,' as used herein, means "reacting' (e) by carboxyl groups: e.g., carboxypyridyl-; or sufficiently bringing together component reactants to (f) by alkoxy groups: e.g., methoxyfuryl-; obtain a chemiluminescent reaction. (g) by amino groups: e.g., dimethylaminotetrahydro The term "peroxidic groups,' as used herein, represents furyl-; "HOO-” “ROO-' or “RCOO-.” “R” is defined in the (h) by sulfo groups: e.g., sulfofuryl-; anhydride below, but in which the “R” in "ROOH' can (IV) Unsaturated alkyl groups: e.g., vinyl-, allyl-, not be aryl. ethynyl-. The term "diluent,' as used herein, means a solvent 10 (B) Other anhydrides, such as: or vehicle which when employed with a solvent does not (a) anhydrides with dicarboxylic acids: e.g., malonic cause insolubility. acid-, glutaric acid, adipic acid; The term "peroxide compound,' as used herein, also (b) cyclic anhydrides with dicarboxylic acid: C.g., includes compounds which upon reaction produce the 15 malonic acid-, glutaric acid-; peroxide group. (c) polymeric anhydrides with dicarboxylic acids: e.g., The term "hydrogen peroxide compound' includes (1) malonic acid-, adipic acid; hydrogen peroxide and (2) hydrogen peroxide-producing (d) anhydrides with acids which are fluorescent: e.g., an compounds. oxalic acid anhydride of 9-carboxy-10-phenyl anthra The anhydride compound of the oxalic acid-type suit 20 able for use in applicants' invention includes a large num cene, fluorescein, 9-carboxyacridine, o-phenoxyphenyl ber of preferred dianhydride compounds in the typical benzoic acid, methylterephthalic acid. formula (RCOOCO(CO)OCOR', in which R and R' For any of the above anhydrides in which R and/or R' may be any aliphatic or aromatic groups, including halo may be any of the typical substituents disclosed, n may gen, or aromatically substituted compounds, for example, 25 also vary, and as stated in the above structural formula, triphenyl substituted methyl groups and in which n is at may be 1 or more. Typical acid anhydrides include oxalic least 1 and may be any number above 1, such as 2, 3, 7, acid anhydride in which n is 1, ketomalonic acid anhy 9, 13 etc. However, other organic oxalic acid anhydrides dride in which n is 2, diketosuccinic acid anhydride in may also be employed. Typical examples follow. which n is 3, triketoglutaric acid anhydride in which n is (A) Anhydrides of the following types: 30 4, tetraketoadipic acid in which n is 5, heptaketoazelaic acid anhydride in which n is 8, undecaketobrassylic acid O O O O anhydride in which n is 12. R-8-0-6(b)n-o C-RH Typical compounds include bistriphenylaceticoxalic an where R or R is: hydride, triketoglutaric-oxalic anhydride, dibenzoic-oxalic 35 anhydride, bis-(4-methoxybenzoic)-oxalic anhydride, di (I) alkyl groups: e.g., decyl-, pentyl-; ethyl-, methyl-, benzoic-tetraketoadipic anhydride, dilauric-oxalic anhy iso-propyl-, cyclohexyl-, etc. or substituted alkyl groups, dride, dipivalic-diketosuccinic anhydride, glutaric-Oxalic by Substituents such as: (a) by aromatic groups: e.g. triphenylmethyl-, di anhydride, bis(2,4-dimethoxybenzoic)-oxalic anhydride, phenylmethyl-, benzyl-; etc. (b) by halogen: e.g., chloromethyl-, chloropentyl-, 40 It should be noted that when R and/or R' are an acyl bromobutyl-; oxy group, and when the acid anhydride is an oxalic acid (c) by acyloxy group: e.g., benzoyloxyethyl-, ace anhydride, the structure of the anhydride could be as fol toxydecyl; lows: (d) by carbonyl groups: e.g., formylmethyl-, pro O O O O O pionylmethyl-; R"--0--0-0---0-R|| || (e) carboxyl group: e.g., carboxymethyl, carboxy in which R'' and/or R' typically could be any of the ethyl-; above stated values for R and R'. This typical compound (f) EY alkoxy group: e.g., ethoxymethyl-, methoxy is thus seen to introduce the concept of a chain type com ethyl-; pound as within the scope of this invention.