User 7a4bd58ff0
14-12-2011 20:41:42
I'm trying to run a Lithium Aluminm Hydride cleavage and reduction of anhydride to alcohols. I'm relying on component level grouping to specify if the SMARTS patterns need to be in the same molecule or not:
([C:1](=O)O[C:2](=O)).([Al]
- )>>[CH2:1][OH].[CH2:2][OH]
However, when I run this reaction backwards on a cyclic anhydride, I get the following error:
chemaxon.reaction.ReactionException: Number of reactants should be 2 instead of 1.
at chemaxon.reaction.Reactor.setReactants(Reactor.java:1210)
But the given component level grouping, with no parentheses, should match either attached or separate alcohols [1]. What's going on?
[1] http://www.daylight.com/dayhtml/doc/theory/theory.smarts.html
ChemAxon afdac7b783
15-12-2011 20:42:53
Onward reactions, both for cyclic and acyclic anhydrides, can be define in Reactor as: ([O:4]=[C:1][O:5][C:2]=[O:3])>>([#6:1][O:4].[#6:2][O:3])
Unfortunately, backward reactions have to be defined separately for intramolecular and intermolecular anhydride formation; Reactor cannot handle different numbers of products in one SMARTS definition.
Examples:
Reduction of acyclic anhydride:
react -r "([O:4]=[C:1][O:5][C:2]=[O:3])>>([#6:1][O:4].[#6:2][O:3])" "[#6]C(=O)OC(=O)CC1CCCC1"
CCO.OCCC1CCCC1
Reverse reaction to produce acyclic anhydride:
react -r "([O:4]=[C:1][O:5][C:2]=[O:3])>>[#6:1][O:4].[#6:2][O:3]" -s "CCO" "OCCC1CCCC1"
CC(=O)OC(=O)CC1CCCC1
Reduction of cyclic anhydride:
react -r "([O:4]=[C:1][O:5][C:2]=[O:3])>>([#6:1][O:4].[#6:2][O:3])" "O=C1CCC(=O)O1"
OCCCCO
Reverse reaction to produce cyclic anhydride:
react -r "([O:4]=[C:1][O:5][C:2]=[O:3])>>([#6:1][O:4].[#6:2][O:3])" -s "OCCCCO"
O=C1CCC(=O)O1