To the greatest extent possible the raw materials for your product are preferably:
- existing items of commerce unencumbered by composition of matter or process claims.
- available in a grade suitable for direct use.
- unencumbered by import restrictions, law enforcement watch lists, and relevant EPA restriction lists.
- TSCA and REACH listed already.
- those free of problematic isomers.
- those not requiring tight fractional distillation to purify.
- free of explosaphors like azide or nitro esters.
Your costs are best contained if your product:
- does not require enantiomeric purity or is not subject to facile isomerism affecting the specification.
- does not require more than one protection/deprotection scheme.
- does not require tight fractional distillation for final purity.
- does not require bulk high pressure chemistry (shops that can do this are limited).
- is air stable.
- is soluble enough in process solvents to maximize space yields (if it is, say, < 10 wt %, batch costs will start to get high).
- does not require solvent changes in a process unit operation.
- is amenable to parallel synthetic strategy.
- does not require serious chilling of the reaction mixture (say, < -20°C).
- has been screened for real purity requirements rather than those based on the desire for tidiness.
- can be isolated by a simple Buchner filtration rather than, say, a centrifuge or other more elaborate solids isolation scheme.
- can be isolated by simple distillation.
He has additional comments, so go read the whole thing -- if you're ever interested in working with a CMO, they're handy tips.