Synthetic procedures provides details for the preparation of compounds, allowing other chemists to be able to repeat the reported work. Experimental procedures routinely use very condensed language to convey a large amount of information using minimal text. procedures typically use very condensed language with chemistry specific verbs conveying the information (e.g. refluxed, recrystallised, extracted), with trained chemists being familiar with these terms.

The style used for experimental procedures does vary across different journals, and it is important to read the author guidelines and familiarise yourself with recent articles for the specific journal the work is being prepared for, and you should consider the information on this page in the context of the specific journal.

Succinct procedures

The use of a succinct language for experimental procedures arose when the printed form was the only means to effectively share information. Printing was expensive, so a very condensed language evolved to minimise costs. The language relies on trained chemists being familiar with common laboratory procedures, and being capable of extrapolating the individual steps involved in a procedure which might be described using only a single word. For instance the phrase "heated to reflux for 1 h" provides sufficient information for a chemist to know how to select and assemble the required glassware and safely heat the reaction without step by step instructions needing to be included in the procedure.

Chemists become familiar with this condensed language approach, typically during undergraduate studies, and learn to recognise the terminology used, and the meaning conveyed in this phraseology. This allows chemists to effectively communicate procedures using minimal language in experimental procedures where steps are following well-established techniques, with only more unusual steps requiring details explanations.

However, care does need to be taken to ensure that procedures do provide sufficient information to avoid ambiguity in procedures. Experimental procedures need to provide enough information to be reliably reproduced. Some common things to consider when preparing a procedure include:

• Do all reagents include quantities

• Are key observations and information on appearances at key points provided

• Is there any crucial safety information that needs to be conveyed (e.g. exotherms, evolution of gas) that could not be easily discerned

• Is sufficient information provided for any purification steps

Single compound preparation

The most commonly encountered procedures are those which describe the preparation of a single, specific compound. This would consist of an entry describing the steps to be performed in chronological order, including quantities used of all reagents, solvents and other materials. The synthetic procedure is usually followed by the compound data listing for the product.

Quantities

Quantities for reagents are usually provided in brackets immediately after the reagent, typically providing the quantities in several different units, which provides some level of redundancy, and makes it easy for readers to understand the reaction stoichiometry. Typically the first unit refers to the measured quantity, e.g. a mass if the compound was weighed, or a volume if added as a liquid. These are then typically followed by molar quantities and equivalents.

e.g. for the addition of benzoic acid (a solid):

• benzoic acid (0.61 g, 5 mmol, 1.0 equiv.)

or for triethylamine (a liquid):

• triethylamine (1.4 mL, 1.01 g, 10 mmol, 2.0 equiv.)

For solvents or common solutions, e.g. aqueous solutions used in workups, usually only a volume is provided:

• 3 M aqueous hydrochloric acid solution (20 mL)

When providing entries, consideration needs to be given to the level of precision being used for the values. In general these should be reflective of the precision used in the laboratory.

Reaction procedure

Isolation

Purification

Product description and quantification

Procedure used for multiple compounds

Where the preparation of a number of related compounds is being described, a general procedure can be used. Here, rather than describing each compound individually, a procedure is written which explains how to prepare the compounds in a general form, then the individual compound entries are limited to reporting the yield and appearance of the specific compound (and compound data listing), without having to repeat the information which is common to all of the related compounds.

Example procedures

Compound

General procedure for the preparation of 

Compound

Following the general procedure, XX (quant) and YY (quant) afforded the title compound as yellow needles (quant).