Methods of making antidegradant compounds are disclosed in which a p-phenylenediamine is reacted with a dicarbonyl to thereby obtain a diimine, which is reduced to obtain mixtures comprising the antidegradant compound.

Methods of making antidegradant compounds are disclosed in which a p-phenylenediamine is reacted with a dicarbonyl to thereby obtain a diimine, which is reduced to obtain mixtures comprising the antidegradant compound.

Methods of making antidegradant compounds are disclosed in which a p-phenylenediamine is reacted with a dicarbonyl to thereby obtain a diimine, which is reduced to obtain mixtures comprising the antidegradant compound.

Antidegradant compounds are disclosed, and methods of making them, that are represented by the formula I:

##STR00001## wherein each X is independently selected from the group consisting of ethyl, methyl, or hydrogen.

Also disclosed are diimine intermediates corresponding to formula III:

##STR00002## wherein each X is independently selected from the group consisting of ethyl, methyl, or hydrogen. These intermediates themselves exhibit antidegradant activity.

Antidegradant compounds are disclosed, and methods of making them, that are represented by the formula I:

##STR00001## wherein each X is independently selected from the group consisting of ethyl, methyl, or hydrogen.

Also disclosed are diimine intermediates corresponding to formula III:

##STR00002## wherein each X is independently selected from the group consisting of ethyl, methyl, or hydrogen. These intermediates themselves exhibit antidegradant activity.

Antidegradant compounds are disclosed, and methods of making them, that are represented by the formula I:

##STR00001## wherein each X is independently selected from the group consisting of ethyl, methyl, or hydrogen.

Also disclosed are diimine intermediates corresponding to formula III:

##STR00002## wherein each X is independently selected from the group consisting of ethyl, methyl, or hydrogen. These intermediates themselves exhibit antidegradant activity.

Provided are a complex prepared from ammonium salt-containing ligands and having such an equilibrium structural formula that the metal center takes a negative charge of 2 or higher, and a method for preparing polycarbonate via copolymerization of an epoxide compound and carbon dioxide using the complex as a catalyst. When the complex is used as a catalyst for copolymerizing an epoxide compound and carbon dioxide, it shows high activity and high selectivity and provides high-molecular weight polycarbonate, and thus easily applicable to commercial processes. In addition, after forming polycarbonate via carbon dioxide/epoxide copolymerization using the complex as a catalyst, the catalyst may be separately recovered from the copolymer.

Provided are a complex prepared from ammonium salt-containing ligands and having such an equilibrium structural formula that the metal center takes a negative charge of 2 or higher, and a method for preparing polycarbonate via copolymerization of an epoxide compound and carbon dioxide using the complex as a catalyst. When the complex is used as a catalyst for copolymerizing an epoxide compound and carbon dioxide, it shows high activity and high selectivity and provides high-molecular weight polycarbonate, and thus easily applicable to commercial processes. In addition, after forming polycarbonate via carbon dioxide/epoxide copolymerization using the complex as a catalyst, the catalyst may be separately recovered from the copolymer.

The present invention provides to an improved process for the preparation of highly pure Erlotinib hydrochloride of formula (I)

##STR00001##

The substantially pure Erlotinib hydrochloride (I) obtained by improved process of the present invention is having purity of greater than 99.8% (% w/w by HPLC).
Erlotinib hydrochloride is useful in the treatment of cancer more particularly in the treatment of lung cancer and pancreatic cancer.

The present invention provides to an improved process for the preparation of highly pure Erlotinib hydrochloride of formula (I)

##STR00001##

The substantially pure Erlotinib hydrochloride (I) obtained by improved process of the present invention is having purity of greater than 99.8% (% w/w by HPLC).
Erlotinib hydrochloride is useful in the treatment of cancer more particularly in the treatment of lung cancer and pancreatic cancer.