Lithium aluminum hydride-Diethylamine

Orders for certain chemicals used to make psychedelics (especially large orders in suspect areas) are sometimes checked by narcs. Indole, lithium aluminum hydride, trimethoxybenzaldehyde, phenyl-2-propanol, diethylamine, olivetol and ergotamine are among those watched. The vast majority of the homologs and analogs described here are, however, legal to manufacture and use. 

Better reagents than lithium aluminum hydride alone are its alkoxy derivatives, especially di- and triethoxyaluminohydrides prepared in situ from lithium aluminum hydride and ethanol in ethereal solutions. The best of all, lithium triethoxyaluminohydride, gave higher yields than its trimethoxy and tris(/er/-butoxy) analogs. When an equimolar quantity of this reagent was added to an ethereal solution of a tertiary amide derived from dimethylamine, diethylamine, W-methylaniline, piperidine, pyrrolidine, aziridine or pyrrole, and the mixture was allowed to react at 0° for 1-1.5 hours aldehydes were isolated in 46-92% yields [95,1107], The reaction proved unsuccessful for the preparation of crotonaldehyde and cinnamaldehyde from the corresponding dimethyl amides [95]. 

Cha et al[12] have reported that acyloxy-9-BBN derivatives are also readily reduced by lithium aluminum hydride in the presence of pyridine, and the reduction stops at the aldehyde stage. Further, Cha and coworkers have found that lithium tris(diethylamino) aluminum hydride (LTDEA), readily prepared [13] from the reaction of LiAlH and 3 equiv of diethylamine in THE (Eq. 7.2), reduces the acyloxy group to the corresponding aldehyde in fair yield. However, in the presence of 2 equiv of pyridine the reduction stops at the aldehyde stage, and hydrolysis affords excellent yields of aldehydes (Eq. 7.3, Table 7.5) [13]. 

---