Todd:Guidelines

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Reaction Numbering Reactions need to be given a unique identifier. The number takes the following form: Your Initials X-Y-Z where X is the reaction type, Y is the attempt number and Z is the page of your lab book where the reaction appears. A reaction type means ‘starting material-arrow-product.’ If you are attempting a certain transformation of a particular starting material to a particular product, then any attempt at that reaction has the same reaction number, regardless of reagents. The reaction also has this number regardless of the outcome. It is the intention that counts. Stereochemistry of products is also important – if the intended stereochemical outcome is different, the reaction has a different number. The numbering of reactions is unique to you, you do not use the same numbers as previous people in the group even if you are repeating their work. Attempt number just increases by 1 each time you do the reaction. Screening several different reaction conditions on small scale on the same page of your lab book can be named with ‘A’ ‘B’ ‘C’ after the full name if so desired, rather than exhaustively giving each reaction a different Y, so e.g. MHT 1-2-3A, MHT 1-2-3B etc. Z is the page number of your lab book where the reaction diagram appears. This number stays the same if the reaction write-up extends over more than one page. In fact it is a good idea to begin each new reaction on the right hand-facing page of the book, allowing overspill at a later date. Example. The first three reactions in MHT’s lab book are shown below. The first reaction here is the first in the lab book. This transformation is given the number ‘1.’ It is the first attempt at this reaction, and appears on page 1, hence it is called ‘MHT 1-1-1.’ The second reaction is the same transformation (remember, regardless of reagents), so also has X = 1. It is the second attempt, and appears on page 3 of the lab book, so has the identifier MHT 1-2-3. The third reaction is a different transformation, so has a different X, and this is the first time it has been done, so Y = 1, and has been entered on page 5 of the lab book, giving MHT 2-1-5. Examples of Reaction Numbering It is a very good idea to keep a tally at the end of your book where you list each transformation separately together with the identifiers of all the attempts along with the yields in each case. Remember the identifier stays the same even if the yield is 0%. For reactions that produce multiple products, and where those products are isolated e.g. by column chromatography, additional numbers may be needed, MHT 1-1-1/1, MHT 1-1-1/2 etc, and the relevant spectra and vials should be labelled as such. Lab Book Write-up DO NOT WRITE NOTES ABOUT WHAT YOU HAVE DONE ON LITTLE BITS OF PAPER When writing your lab book, you should include all details, but in a concise manner. The reason for keeping a lab book is so that the people who come after you can understand and replicate what you have done. You are writing it for them, not for me. Your lab book must be written in pen, not pencil. You must never remove or add pages. Mistakes must be crossed out lightly, so that they may still be read. Do not use white-out/Tippex. All lab book pages must be dated somewhere, and when complete, should be signed. Ideally periodically you should get another member of the group to sign and date your lab book pages. All relevant TLC’s must also be drawn in pen, and RF values given to two decimal places, as well as the solvent system used for each. (Drawing TLC’s allows you to throw away your TLC plates) The first line of the write up for each reaction can have a brief remark about the reason for doing the reaction, to aid your memory when you come to write up your work, e.g. ‘Scale-up of MHT 5-4-36’ or ‘MHT 7-4-98 at increased temp.’ The write up should look something like this: Examples of Lab Book Write-up