DABCO dianions

Lactams.1 A new synthesis of 0-lactams involves oxidative coupling of dianions of acyclic amides such as 1, prepared as shown from p-anisidine (equation I). The amide 1 is converted into the dianion by BuLi (2 equiv.) and DABCO or by t-... 

Reaction of ethyl 2,5-butadienoate with aldehydes.1 This ester (1) reacts with propionaldehyde in ether at 23° in the presence of DABCO to provide 2 in 42% yield, formed by replacement of the a-proton of 1. This condensation can also be effected with butyllithium, but then 2 is accompanied by 3, formed via a dianion of 1. 

The absence of catalytic cleavage of nonionized phthalimide in the presence of carbonate buffer solution cannot be attributed to the steric requirement of carbonate dianion, because trimethylamine and DABCO may be considered to have the same or even more steric requirements than carbonate dianion. The most... 

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