Büro für Altlastenerkundung und Umweltforschung

Dr. Rainer Haas

Stadtwaldstr. 45a, D-35037 Marburg, Tel.: 06421/93084, Fax: 06421/93073

email: haasr@gmx.net

Chemical reactions of chlorovinylarsines (Lewisite)

1. Reaction of 2,2-Dichlorodivinylarsine chloride (Lewisite II) with Alcohols

Rainer Haas¹, Alfred Krippendorf², Klaus Steinbach³

1: Buero fuer Altlastenerkundung und Umweltforschung, Stadtwaldstrasse 45a, D-35037 Marburg, Germany

2: Hazard Control Ltd., Versuchsfeld Trauen, D-29328 Fassberg, Germany

3: Philipps-Universitaet Marburg, FB Chemie, Hans-Meerwein-Strasse, D-35032 Marburg, Germany

Translation, original article was published in UWSF - Z Umweltchem. Oekotox. 10 (2) 64-65 (1998), ecomed publishers D-86899 Landsberg, Germany

Abstract

2,2-Dichlorodivinylarsine chloride (Lewisite II) reacts by room temperature quickly upon alcohols in an equilibrium reaction to yield 2,2-Dichlorodivinylarsine ether. The reactions are not quantitative. The methyl-, ethyl- and propyl ether are not stable.

Key words: analysis, arsenical compounds, chemical warfare agents, cwa, chemical reactions, dichlorodivinlyarsine chloride, lewisite

1 Introduction

Chlorovinylarsines were synthesised at the first time from GRIFFIN 1904. During WW I investigations for using Lewisites as chemical warfare agents were done in Germany and USA. During WW II Lewisite I was produced in some countries.

The technical product of Lewisite I includes about 10-15% of Lewisite II and a small amount of Lewisite III (1).

2 Experimental

2,2-Dichlorodivinylarsine chloride (Lewisite II, CAS-No. 40334-69-8) was derivatizied with the following alcohols: methanol (MeOH), ethanol (EtOH), 1-propanol (1PrOH), 2-propanol (2PrOH), 1-butanol (1BuOH), 2-butanol (2BuOH), 1-pentanol (1PeOH), 2-pentanol (2PeOH), 3-pentanol (3-PeOH), 1-hexanol (1HexOH), 2-hexanol (2-HexOH), 1-heptanol (1HepOH), 2-heptanol (2HepOH), 3-heptanol (3-HepOH), 1-octanol (1OcOH), 2-octanol (2OcOH) and 3-octanol (3OcOH).

For the derivatization procedures acetonic solutions of Lewisite II 70 µg/ml and of the different alcohols with 40 mg/ml were used. Derivatizations were done in 1.4 ml vials at a temperature of 20°C.

For the separation of the Lewisite II-alcohol derivatives a gas chromatograph HP 5890 with HP 7673 autosampler and electron capture detector (ECD) was used. Analysis were done under the following chromatographic conditions:

column: capillary column DB 5, length 30 m, thickness 0.25 mm

carrier gas: nitrogen

column temperature: initial 100°C (1 min), 10°C/min to 230°C, 230°C (6 min)

injector temperature: 250°C

detector temperature: 300°C

injection volume: 1 µl.

Three minutes after adding of alcohols analysis were started, continously repeated within three days and sometimes repeated within the next three weeks (stabilization control). Identifications of the derivatives were done by gas chromatography/mass spectrometry (GC/MS).

3 Results and discussion

2,2-Dichlorodivinylarsine chloride reacts upon alcohols like

(Cl(CH=CH))₂AsCl + ROH --> (Cl(CH=CH))₂AsOR + HCl

by creating 2,2-Dichlorodivinylarsinether.

There are retention times (R_t), limits of detection (LOD) and equilibrium concentrations of all alcohol derivatives presented in table 1.

Table 1: Retention times (R_t), limits of detection (LOD) and equilibrium concentration of alcohol derivatives (EC); alcohol concentration: 4%

The methyl-, ethyl- and propyl ether are not stable at an alcohol concentration of 40 mg/ml. They decomposite within 6 to 12 hours to undetectable products. With an alcohol concentration of 250 mg/ml the methyl and ethyl ether are stable for more than 72 hours. With the other alcohols a stable equilibrium between Lewisite II and the alcohol derivatives is created. The equilibrium concentrations are reached within 30 min. The reaction products are stable. Both, Lewisite II and the alcohol derivatives, can be detected with gas chromatography and electron capture detector (GC/ECD).

With gas chromatography/mass spectrometry the following derivatives were identified:

• 2,2-Dichlorodivinylarsine methylether from methanol

• 2,2-Dichlorodivinylarsine ethlyether from ethanol

• 2,2-Dichlorodivinylarsine propylether from propanol

• 2,2-Dichlorodivinylarsine butylether from butanol

• 2,2-Dichlorodivinylarsine pentylether from pentanol

• 2,2-Dichlorodivinylarsine heptylether from heptanol

• 2,2-Dichlorodivinylarsine octylether from octanol.

From a mixture of Lewisite II and different alcohols all possible products were created. From a mixture of Lewisite II, alcohols and thiols only the more stable Dichlorodivinylarsine thioether were detected.

The equilibrium concentrations between Lewisite II and the 2,2-Dichlorodivinylarsine ether depend on the alcohol concentration in the solution. Investigations were done with 1-butanol; the following equilibrium concentrations of Lewisite II were detected:

• 54,6% Lewisite II with 5% 1-butanol

• 44,6% Lewisite II with 10% 1-butanol

• 33,2% with 25% 1-butanol

• 18,8% with 50% 1-butanol.

4 Literature

1. Martinetz, D.; Rippen, G. (1996): Handbuch Ruestungsaltlasten. ecomed, Landsberg

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