Carbon disulfide (18 ml, 0.3 mol) was introduced into the flask through the dropping funnel.
A solution of zinc chloride (2 g, 0.15 mol) in a mixture of 40-ml concentrated ammonium hydroxide and 50 ml of methanol was then added through the dropping funnel.
As a precaution, ice was added to the cooling bath and 40 ml methanol and 50 ml deionized water, which is degassed by applying vacuum, were then added rapidly through the dropping funnel.
6 mmol (1.5 eq). of sodium nitrite in 5 mL cold distilled water was added dropwise through the dropping funnel to the solution and stirred in an ice bath for 5 min (Fig. 1a, step I).
While stirring the mixture, 40 mmol KOH dissolved in 40 ml water was rapidly added through the dropping funnel while the temperature was maintained at 50°C.
A solution of 21 mmol acid chloride dissolved in 10 ml tetrahydrofuran was added slowly through the dropping funnel at such a rate that the temperature did not rise above 40°C.
PARIS — As I traveled in a taxi on a rainy Monday, the Place de la Concorde came into view through the drops on the window.
A drop of solution containing an allergen will be placed on Daniel's skin, which will be pricked with a needle through the drop.
By selecting an author through the drop-down menu, users can view a list of messages written by the author.
