Lithium aluminum hydride amine adducts

Iodine azide, on the other hand, forms pure adducts with A -, A - and A -steroids by a mechanism analogous to that proposed for iodine isocyanate additions. Reduction of such adducts can lead to aziridines. However, most reducing agents effect elimination of the elements of iodine azide from the /mwj -diaxial adducts of the A - and A -olefins rather than reduction of the azide function to the iodo amine. Thus, this sequence appears to be of little value for the synthesis of A-, B- or C-ring aziridines. It is worthy to note that based on experience with nonsteroidal systems the application of electrophilic reducing agents such as diborane or lithium aluminum hydride-aluminum chloride may yet prove effective for the desired reduction. Lithium aluminum hydride accomplishes aziridine formation from the A -adducts, Le., 16 -azido-17a-iodoandrostanes (97) in a one-step reaction. The scope of this addition has been considerably enhanced by the recent... 

A thio-substituted, quaternary ammonium salt can be synthesized by the Michael addition of an alkyl thiol to acrylamide in the presence of benzyl trimethyl ammonium hydroxide as a catalyst [793-795]. The reaction leads to the crystallization of the adducts in essentially quantitative yield. Reduction of the amides by lithium aluminum hydride in tetrahydrofuran solution produces the desired amines, which are converted to desired halide by reaction of the methyl iodide with the amines. The inhibitor is useful in controlling corrosion such as that caused by CO2 and H2S. 

N-Methylethylamine has been prepared by heating ethyl-amine with methyl iodide in alcohol at 100° 3 by the hydrolysis of N-methyl-N-ethylarenesulfonamides,4-5 -nitroso-N-methyl-N-ethylaniline,6 or methylethylbenzhydrylidene ammonium iodide 7 by catalytic hydrogenation of ethyl isocyanate or ethyl isocyanide 8 and by the reduction of ethyl isocyanate by lithium aluminum hydride,9 of N-methylacetisoaldoxime by sodium amalgam and acetic acid,10 or of a nitromethane/ethylmagnesium bromide adduct by zinc and hydrochloric acid.11... 

Ruff et al. in a series of publications described the synthesis of amine complexes of aluminum hydride [32, 33]. Their study investigated the reaction of these materials with typical Lewis bases in order to define the conditions for the stability of aluminum hydride derivatives in which the aluminum atom exhibits a coordination number of five. They first described methods for making tertiary alkyl amine complexes of aluminum hydride utilizing lithium aluminum hydride and an amine hydrochloride. A finely ground lithium aluminum hydride was placed together with trimethylammonium chloride (ratio 1 2). They prepared other trialkylamine alanes and the N-dialkylaminoalanes, in a similar fashion. These adducts of alane were found to sublime readily at temperatures up to 40 °C except for the tri-n-propylamine alane, which sublimed very slowly and could also be recrystallized from hexane at — 80 °C. 

The cis addition of nitrosyl chloride to cyclic unconjugated polyenes was observed in dichloromethane28. From cyclooctadiene a single diastereomeric dimer 3 (either meso or dl) was produced due to conformational factors associated with the cis configuration. This product underwent transannular electrophilic reaction to give 4. From (Z,Z,Z)-l,5,9-cyclododecatriene the chloro nitroso adduct 5 was obtained as a mixture of the meso and dl forms and was converted to -chloro amine 6 by lithium aluminum hydride/aluminum trichloride reduction 6 was converted to the corresponding aziridine. 13C-NMR spectroscopy was extremely useful in determining the diastereomeric composition of the nitroso dimers. 

The direct oxidation of the tr-adduct 1 with bromine, A -bromosuccinimide or, preferably, lead tetraacetate in the presence of acetic acid afforded jS-acetoxy amines 2 by an overall syn addition. The acetate reduction with lithium aluminum hydride gave the corresponding )S-hy-droxy amines 360 62. 

The only asymmetric synthesis of the Nuphar indolizidine to date is due to Barluenga and co-workers (615). Their route to the (5S,8 ,8aS)-( -) enantiomer of 944 commenced with cycloaddition between the proline-derived 2-amino-butadiene 957 and imine 958 (Scheme 125). Hydrolysis of the adduct 959 gave piperidinone 960 in 51% yield and an ee of better than 99%. Once the alcohol and amine groups had been mutually protected as the cyclic carbamate 961, defimctionalization of the ketone was accomplished via an enol triflate. Chain-extension of the deprotected piperidine 962 at the hydroxymethyl substituent afforded 963, which was cyclized to the bicyclic lactam 964 simply by heating in toluene. Reduction with lithium aluminum hydride completed the synthesis of ( - )-944 ([a]n -99°, c 1.3, CH2CI2). 

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