lized from hot water, filtered, and air dried. The overall
yield ofchloroacetamide was 1.8 g (64%). The white needles
filtration process required 10 min at 8000 rpm. It was
accomplished with a microcentrifuge (Fisher Scientific).
Small snap-cap plastic tubes (Eppendorf tubes) containing
a 0.45-µm filter were convenient. Note: Unwashed plastic
tubes from Rainin Instrument showed resonances at δ 63
and 73 in the filtrate. Tubes from Micron Supplies
Incorporated did not.
1
3
had melting point of 118.5-119. C-NMR: ClCH2, δ 42,
d; CONH2, δ 172, d. Note: The more direct reaction of the
acid chloride with ammonium acetate in acetone (7) yielded
only 31% of the amide.
1
3
[
1,2- C]Chloroacetonitrile (CCN). To a 25-mL three-
necked flask equipped with good mechanical stirring, a
small distillation head, and a receiver was added 1.3 g (0.014
mol) of [1,2- C]chloroacetamide. The flask was brought
to 130 °C and held there until all of the amide had melted.
The receiver was immersed in an ice bath, and a slurry of
Two milliliters of seawater and lake water as well as
sediment and sludge slurries was incubated without dilution
with 2 µL of a 1 M probe in DMF. The slurries were shaken
before removing the sample. The clear seawater and lake
water samples required no centrifugation or filtration. The
sediment slurries were centrifuged and filtered before NMR
analysis as described above for soil. For “anaerobic”
incubations, unless otherwise stated, the tubes were gassed
briefly (30 s) with hydrogen. As the results indicate, the
samples were not completely anaerobic. This procedure
allowed anaerobic transformations (reductions) to occur
without completely suppressing oxidative reactions.
The NMR analysis was an overnight acquisition (16 h)
on a General Electric QE-300 spectrometer. The partial
percent conversions were estimated from relative intensities
1
3
1
.9 g of phosphorous pentoxide (0.014 mol) in 2 mL of
freshly distilled 1,2,4-trichlorobenzene was added all at
once. With vigorous stirring, the flask was brought to 140-
1
50 °C for 0.5 h and then rapidly to 175 °C for another 0.5
1
3
h. The water white [1,2- C]chloroacetonitrile liquid, 0.4
g, was obtained in 37% yield. C-NMR: ClCH2, δ 25, d;
CN, δ 117, d.
1
3
The chemical shifts for products have been given
1
3
elsewhere (5, 6) and are indicated in the figures. The C-
1
3
C coupling constants were ∼2 Hz.
-
Environm ental Sam ples. (a) Soils. Two soil samples
of the R-carbon resonances except for HCO3 . This
were employed. Both were taken from a dump site at UCR
d.S soil) that had been exposed to haloorganics and other
conversion was estimated from the relative intensities of
the HCO3 resonances as compared to the CdO or CtN
-
(
pesticides for some time. The d.S-1 sample represents a
homogenate of a 2-ft deep core taken from the center of
the site. The d.S-2 sample was obtained from the edge of
the site. A sample of d.S-1 was held for 1 yr at 5 °C (d.s-1,
resonances of the starting probe or product. These latter
are tertiary carbons and not subject to the NOE (nuclear
Overhauser effect) enchancement attendant upon decou-
pling the proton resonances with irradiation (8). Hence,
the corresponding resonances are less intense than those
associated with the R-CH2X (X ) Cl, OH) carbons. Based
upon the close similarity of authentic spectra of the probes
taken under the conditions described, we take the inherent
intensities of these R-carbons as the same for the purpose
of estimating product distribution. Similarly, and upon
the same basis, all tertiary carbons are taken as having the
same (lesser) intensity in any given sample. Thus, percent
conversions were determined on this basis. In samples
where both the tertiary and R-carbons were discernible,
relative distributions calculated using either set of carbon
intensities were the same ((5). The reproducibility of the
distributions obtained from replicate samples for any
analysis was within 10%ofthe values reported. This analysis
1
-yr-old) to test any changes in reactivity upon storage.
b) Marine Coastal Water and Sediments. These sea
(
samples were taken from Shaw’s Cove in Laguna Beach,
California. Sea water was taken about 100 yards from shore
at the surface. In addition, two samples of sediments were
collected. The first, Shaw’s Cove 1 (SC-1), was a grayish
sandy sediment from the top 2 in. of the surface bottom
at a depth of 30 ft. The second (SC-2) was a dark, near
blackish silty sediment taken at a depth of 40 ft from 3 to
5
in. below the surface bottom. These samples were slurries
containing about a two-thirds liquid phase.
c) Lake Samples and Sediments. These were taken from
(
Lake Perris, Riverside, CA. Lake water (LPW) was a surface
sample, and the sediments LP-1 and LP-2 represent an
upper sandy sediment (top 1-2 in.) taken at a depth of 20
ft and a lower black silty sand collected at 4-6 in. below
the surface bottom at a depth of 12 ft. These slurries were
about two-thirds liquid.
1
3
assumes that all C-labeled carbons are equally visible in
the centrifugate (no selective adsorption to the environ-
mental matrix) and that the distribution of products
observed is the true distribution. In essence, we assume
that these highly water-soluble probes and products have
large distribution coefficients such that their presence in
(
d) Activated Sludge. The sample of activated sludge
(
AS) was collected from the aeration tank at the Riverside
-
3
City sewage plant. The blackish slurry contained about
one-third solid by volume.
water is greatly favored at 10 M. This assumption is
buttressed by the observation that the spectra of the probes
1
3
Analyses. For soil, the following protocol was used: 1.0
g of sample was triturated with 2 mL of glass distilled water,
and C-labeled bicarbonate exposed to the approximate
2:1 water/ samples, where no reaction was detected, ex-
hibited the same NMR spectrum (following centrifugation/
filtration) as authentic standards at that concentration.
However, poorly resolved spectra indicated solids in the
analyte and/ or adsorption to them (this work shown in
Figure 3a,b) or perhaps soluble organic matter (5). These
spectra were greatly refined by the addition of acid. We
presume this result, in part, reflects the desorption ofanions
from the solid matrices.
1
3
and 2 µL of a 1 M C probe in dimethylformamide (DMF)
was added. The 30-mL volume test tube containing the
reactants was capped with a serum cap, and samples were
allowed to stand in a rack at room temperature. They were
shaken once each day by hand. For anaerobic incubations
(
see below), the same procedure was employed except that
the tube was gassed with hydrogen. At the desired time,
approximately 1 mL (or all) of the slurry was centrifuged/
filtered. The clear centrifugate (0.5-0.6 mL) was transferred
to a serum capped NMR tube, and 100 µL of D2O/ mL of
sample was added for the lock. Samples were held at 5 °C
until the NMR acquisition could begin. The centrifuge-
Chloride analysis was accomplished by direct potenti-
ometry at high ionic strength employing an Orion chloride
ion electrode and a Calomel double-jacketed reference
electrode as previously described (9).
1
1 8 6
9
ENVIRONMENTAL SCIENCE & TECHNOLOGY / VOL. 30, NO. 4, 1996