A preparation method for a trans-cyclobutane-o-dicarboxylic acid ester and a derivative thereof includes the following steps: in an organic solvent, catalyzing a substrate with a structure as shown in a structural formula I by using organic alkali at 50-90° C. so as to generate isomerization, acquiring the trans-cyclobutane-o-dicarboxylic acid ester or the derivative thereof, herein the structural formula I is as follows:

##STR00001##

Each R.sup.1, R.sup.2, R.sup.3 and R.sup.4 is independently one of hydrogen or an alkyl of C.sub.1-C.sub.5, and each of R.sup.5 and R.sup.6 is independently one of alkyl of C.sub.1-C.sub.10 and benzyl.

A preparation method for a trans-cyclobutane-o-dicarboxylic acid ester and a derivative thereof includes the following steps: in an organic solvent, catalyzing a substrate with a structure as shown in a structural formula I by using organic alkali at 50-90° C. so as to generate isomerization, acquiring the trans-cyclobutane-o-dicarboxylic acid ester or the derivative thereof, herein the structural formula I is as follows:

##STR00001##

Each R.sup.1, R.sup.2, R.sup.3 and R.sup.4 is independently one of hydrogen or an alkyl of C.sub.1-C.sub.5, and each of R.sup.5 and R.sup.6 is independently one of alkyl of C.sub.1-C.sub.10 and benzyl.

The present invention relates to a carbon sorbent the can selectively remove platinum-group metals and other heavy metals such as tin without co-removing organic synthesis products including pharmaceutical intermediates and finished Active Pharmaceutical Ingredients (APIs). The carbon sorbents of the present invention are made from low-cost, high purity starting materials and the resulting carbon sorbents are also very pure. The carbon sorbents possess a combination of certain nitrogen and phosphorous groups combined with mesoporosity (2 to 50 nm diameter pores) that proves the high metal adsorption.

The present invention relates to a carbon sorbent the can selectively remove platinum-group metals and other heavy metals such as tin without co-removing organic synthesis products including pharmaceutical intermediates and finished Active Pharmaceutical Ingredients (APIs). The carbon sorbents of the present invention are made from low-cost, high purity starting materials and the resulting carbon sorbents are also very pure. The carbon sorbents possess a combination of certain nitrogen and phosphorous groups combined with mesoporosity (2 to 50 nm diameter pores) that proves the high metal adsorption.

Provided are methods for the production of phthalic acid (PA), isophthalic acid (IP A), terephthalic acid (TP A), and derivatives thereof. The methods are based on the addition of beta propiolactone to furfural or a derivative thereof. Provided are cost effective routes to biobased IP A and derivatives thereof, including terephthalic acid.

Provided are methods for the production of phthalic acid (PA), isophthalic acid (IP A), terephthalic acid (TP A), and derivatives thereof. The methods are based on the addition of beta propiolactone to furfural or a derivative thereof. Provided are cost effective routes to biobased IP A and derivatives thereof, including terephthalic acid.

Provided are methods for the production of phthalic acid (PA), isophthalic acid (IP A), terephthalic acid (TP A), and derivatives thereof. The methods are based on the addition of beta propiolactone to furfural or a derivative thereof. Provided are cost effective routes to biobased IP A and derivatives thereof, including terephthalic acid.

Provided are methods for the production of isophthalic acid (IP A) and derivatives thereof. The methods are based on the addition of beta propiolactone to furfural or a derivative thereof. Provided are cost effective routes to biobased IP A and derivatives thereof, including terephthalic acid.

Provided are methods for the production of isophthalic acid (IP A) and derivatives thereof. The methods are based on the addition of beta propiolactone to furfural or a derivative thereof. Provided are cost effective routes to biobased IP A and derivatives thereof, including terephthalic acid.

Provided are methods for the production of isophthalic acid (IP A) and derivatives thereof. The methods are based on the addition of beta propiolactone to furfural or a derivative thereof. Provided are cost effective routes to biobased IP A and derivatives thereof, including terephthalic acid.