The use of carrier adsorption permanganate for deamination reactions represents a new method, with relevant results published in US Patent 5919672 on July 6, 1999 (CA1999131: 72765). ShankarBB describes a process for preparing (4-fluorophenyl)-3-(R)-(a-3-(S)-hydroxy-3-propyl)-4(S)-a-(4-hydroxyphenyl)-2-azetidinone. This is detailed in US Patent 5856473 issued January 5, 1999 (CA1999130: 110148).
ShankarBB also outlines a process for the preparation of (4-fluorophenyl)-3-(3-hydroxypropyl)-4(S)-(4-hydroxyphenyl)-2-azetidinone, as described in WO 9716424 from May 22, 1997 (CA1997127: 17572). ChiuJS, ColonC, AbercrombieNetherlands, FuXY, et al., present a process for the synthesis of azetidinones in US Patent 6207822 issued March 27, 2001 (CA2001134: 252201).
DillaneAB, MaryAC, MartinSD, et al., discuss the synthesis of iodinated biochemical tools related to the azetidinone class of cholesterol absorption inhibitors in Bioorg Med Chem Lett. 2002;12:311-314.
A new method using carrier adsorption of high medullary potassium permanganate for amino reactions was introduced by Bar-mallDC in 2003, where potassium permanganate loaded with ferrous sulfate heptahydrate acts as a heterogeneous oxidation agent. This method allows for the simple, effective, and selective oxidation of aromatic amines into azo compounds, and fatty amines are oxidized into corresponding carbonyl compounds with yields ranging from 80% to 96%.
For efficient synthesis of 3-substituted pyridine derivatives, CaiDW in 2002 demonstrated that reacting pyridine with n-BuLi generates lithium pyridine reactive intermediates. These intermediates then react with triisopropyl borate to produce 3-boronic acids with an 87% yield. Reactions with other electrophilic reagents generate 3-substituted pyridine derivatives, yielding 88% to 94% across four cases.
Monoacyl derivatives of piperazine can be synthesized mildly and quickly, as shown by BandgerBP in Tetrahedron Lett. 2003. By condensing chloro-4,6-dimethoxy-1,3,5-triazine or morpholine in dichloromethane with carboxylic acid activation, a series of white single acylation piperazine derivatives are produced at room temperature. The method features mild conditions, short reaction times, and yields between 60% to 95% across five cases.
VyasPV details a reaction involving aromatic amines, aromatic hydrocarbons (including naphthalene, anthracene, pyrene), and naphthol in hydrochloric acid or hydrogen bromide solution with the addition of 30% hydrogen peroxide. Active chlorine or bromine generated in situ can conveniently and effectively convert these compounds into chlorinated or brominated products. This method is clean and safe, with yields up to 75%.
GowdaS discusses the selective reduction of aliphatic and aromatic nitro compounds using zinc dust and formic acid at room temperature within 2-5 minutes, generating corresponding amino compounds. Across 42 cases, yields range from 75% to 95%.
These advancements provide cleaner, more efficient, and higher-yielding methods for various chemical syntheses.