Best online chemical reference database?

Hey, i'm looking for a really good (professional quality) online chemical database. I'm talking about melting point, boiling point, structure (3d with stereogenic centers), refractive index (when applicable), density, description of pure solid (including common salts for for pharms), solubility in different solvents, mol. weight (duh), etc.

I currently am using the Merck Index online by Cambridgesoft, and it's pretty good (the plugin that lets you create a molecule on your own and search for it is neat), but the way the information is presented is not consistent and sometimes has glaring omissions (such as melting point). Another thing that really annoys me is that for the pharms for example sometimes they will have one entry for both enantiomers, sometimes they'll say which enantiomer is active (sometimes not). Then when they name the enantiomer they sometimes will only include the L - D naming, which is impossible to figure out which name correlates to which structure unless i know how each structure rotates a plane of light (in other words, R - S naming is a must).

Anyway, if anyone knows of a good one, please let me know, thanks.

 

gotta be erowid. hands down.

www.erowid.org

 

I think he's looking for more of an overall reference source for chemical properties.

I use a hardbound Merck 12th and CRC 78th. for all practical purposes, they tell me pretty much all I need to know; anything not printed, I just search for it online.

If you're using CambridgeSoft, you probably already know about http://chemfinder.com

 

Yeah, i'm looking for an in depth ALL chemical database, not just psychoactives. But yeah, i have used chemfinder, and it's decent for most things, but there are some conflicts between it and Merck index for things such as melting point and in one case the difference was enough to cause a disparity in my results (chemfinder said one thing, Merck said another)...

Also, in sorta the same area, does anyone know where i can find literature values for the experimental yield of various organic reactions? For example, if i get a 35% yield from a reaction, i'd like to know it's because the reaction experimentally only yields 40% anyway, or if i just messed up somewhere.

Thanks for all the input so far, and thanks in advance for any more help.

 

melting points will sometimes differ from source to source; this is due to instrumentation and temperature gradients, not to mention purity (or lack thereof) of compounds.

also, melting point ranges, rather than exact melting points, should be observed in practice.

if you got 35% yield for a procedure that averages 40%, that's nothing to really be concerned about.