(4.2g) produced N,N-diethyl-4-methylbenzamide (4.5a) in moderate yield (44%). A

moderate yield (51%) was also obtained for N,N-diethylfuran-2-amine (4.5g) from N,N-

diethylamine. These results show that the cyclic aliphatic amines, e.g., tetrahydro-1H-

pyrrole, produce the secondary amides in much better yields than the acyclic aliphatic

amines, e.g., N,N-diethylamine.

Table 4-4. Preparation of tertiary amides 4.5a-k
 4.5 R R2 R3 Yield (%) mp (oC) mplit'(C)
 a 4-CH3C6H4 C2H5 C2H5 44 oil oil
 b 4-CH3C6H4 i-Pr C2H5 0
 c 4-CH3C6H4 i-Pr i-Pr 0
 d 4-02NC6H4 -(CH2)4- 96 73-74 b
 e C6H5 -(CH2)4- 100 oil oil[86AG(Int)565]
 f 2-CH30C6H4 -(CH2)4- 98 oil b
 g 2-furanyl C2H5 C2H5 51 oil oil[71CC733]
 h 1-naphthyl -(CH2)4- 94 51-52 b
 i 4-pyridinyl -(CH2)4- 100 oil b
 j PhCH2 -(CH2)4- 99 oil oil[89TL2771]
 k Ph2CH -(CH2)5- 68 114-116 b
 "Cadogan J. I. G. et al, Dictionary of Organic Compounds, Sixth edition, Chapman & Hall, London, UK.
 4.5a, M-01138; bNovel compound.


4.2.5 Preparation of a-Hydroxyamides using BtSO2CH3.

 Development of synthetic methods for a-hydroxyamides has attracted considerable

interest, since they include valuable therapeutic agents and also possess synthetic utility.

General routes to a-hydroxyamides include: i) the reduction of a-keto-amides with

sodium borohydride, [82CC1282] [85JCS(P1)769] [90CC1321] with other metal

borohydrides, such as LiBEt3H, KBEt3H and Zn(BH4)2 [87CL2021] or with magnesium-

or titanium-based reagents; [90BCS(Jpn)1894] ii) the hydrogenation of a-keto-amides in

the presence of palladium on charcoal [84BCS(Jpn)3203] or neutral rhodium (I)

complexes [84CL1603] [86CL737] [88TL3675]; iii) the oxidation of acyclic, tetra-

substituted amide-enolates by oxaziridines with yields of around 50%. [87JOC5288]