Acyl bromides hydroxy

The Heck reaction on polymer-bound iodoarenes is assisted by the addition of a catalytic amount of tetra-n-butylammonium bromide and has been employed in the synthesis of 4-carboxycinnamic esters and amides [33], and 4-aminosulphonyl-cinnamic esters [34], It has also been reported that the presence of an equimolar equivalent of benzyltriethylammonium chloride aids the Pd(II)-mediated reaction of A -acyl-2-iodoanilines with vinylidene carbonate, which leads to A -acyl-2-hydroxy-indolines providing a convenient route to the indoles (80-90%) [35], The catalysed reaction of 2-hydroxy- and 2-tosylaminoiodobenzene with 1,2-dienes produces 1,2-dihydrobenzofurans and 1,2-dihydroindoles, respectively [36]. 

Acetylenedimagnesium bromide, 66, 84, 137 Acyl-alkyl diradical disproportionations, 299 Acyl-alkyl diradical recombination, 296 Alkaline hydrogen peroxide, 10, 12, 20 Alkylation of formyl ketones, 93 Alkylation via enolate anions, 86 17a-Alkynyl steroids from 17-ketones, 67 2a-Al]yl-17jS-hydroxy-5a-androstan-3 -one, 9 5 Allylic acetoxylation, 242 Allylmagnesium bromide, 64 17 -Aminoandrost-5-en-3 -ol, 145 17 a-Aminomethy 1-5 a-androstane-3, 1718-diol, 387... 

When the 3-thiourea derivative (59) was heated in boiling ethanol for 3 h, and then the evaporated reaction mixture was treated with 10% NaOH solution at 100°C for 20 min, anhydro 2-methyl-3-mercapto-4-hydroxy-5,6,7,8-tetrahydro[l,2-6]pyridazinium hydroxide (61) was obtained (71CPB159). The mercapto group was alkylated with benzyl bromide and was treated with HgCla in boiling ethanol to yield the 3-chloromercurithio derivative. Anhydro 3,4-dihydroxy-2-methyl-5,6,7,8-tetrahydropyrido[l,2-f ]pyridazinium hydroxide (62) was O-acylated with acetic anhydride, but the structure of the product was not elucidated (71CPB159). 

The imino group of the spiro derivative (53) was hydrolyzed to an oxo group (91SL44). The hydroxy group of 2-hydroxymethylperhydropy-rido[2,l-b][l,3]oxazines was alkylated and acylated with benzyl bromide in... 

The hydroxy group of 2-(2-hydroxyethyl)-l,2,3,6,7,116-hexahydro-4//-pyrazino[2,l-a]isoquinoline reacted with acyl chlorides and propargyl bromide (65BEP659249). Hydroxy groups of 2-benzoyl-9,10-dihydroxy-l,2,3,6,7,116-hexahydro-4//-pyrazino[2,l- ]isoquinolin-4-one, obtained from... 

The organoindium reagent, prepared from indium metal and bromoacetonitrile, reacts with carbonyl compounds in the presence of chlorotrimethylsilane to give /3-hydroxy nitriles (Scheme 93),336 337 Similarly, indium-mediated coupling of bromoacetonitrile or 2-bromopropionitrile with a variety of aromatic acyl cyanides affords the corresponding aromatic a-cyanoketones in moderate to good yields under mild and neutral conditions (Equation (86)).338 Carbonyl compounds are efficiently transformed into 2,2-dichloro-3-hydroxynitriles by the action of trichloroaceto-nitrile and indium(i) bromide (Scheme 94).339 Bromocyanomethylation of carbonyl compounds is also achieved by the reaction of dibromoacetonitrile and indium(i) bromide.340... 

The Leukart reaction has also been used in the conversion of dehydroepiandro-sterone into 17/3-formylamino-3/3-formyloxyandrost-5-ene, which on reduction with lithium aluminium hydride afforded 3/3-hydroxy-17/3-me thylaminoandrost-5-ene. Acylation with isocaproyl chloride then furnished the N-methyl-N-isocaproyl steroid (197), after selective ester hydrolysis of the initially formed ON-diacyl derivative. The amide (197) was further converted into its 3,5-cyclo-6-ketone via the 3,5-cyclo-6/3-alcohol and thence by reaction with hydrogen bromide into the corresponding 3/3-bromo-5a-6-ketone which upon dehydrobromination furnished a A2-5a-6-ketone and ultimately the 2-monoacetate of the 2/3,3/3-diol (198) after reaction with silver acetate and iodine. Hydrolysis to the 2/3,3/3-diol (198) gave a separable mixture of the 2/3,3/8-dihydroxy-5a- and -5/3-ketones.88... 

Acyl phosphonates (444) have been converted into tertiary a-hydroxy al-kenylphosphonates (445) through an indium mediated allylation. The allylation proceeds equally well with different allylic bromides and does not appear to be sensitive to steric hindrance at the p-carbon atom (Figure 82)/ ... 

In a similar way, when ethylene bromide is treated with silver acetate, CH3—COOAg, an acyl-ester of the corresponding di-hydroxy alcohol is obtained, which, on hydrolysis, yields the di-hydroxy alcohol itself, as follows ... 

One example of a mono-O-alkylation has been described so far. The reaction of H with p-methylbenzyl bromide in a 1 1 molar ratio resulted in the chiral resorcarene monoether 77a, which was exhaustively acylated to give resorcarene 77b containing one alkoxy and seven acetoxy groups . Recently, the chiral resorcarene 77d was obtained in the form of the pure enantiomers by monoacylation of H with camphorsulphonyl chloride, separation of the crude mixture by HPLC (11% for each diastereomer 77c), exhaustive O-methylation of the remaining hydroxy groups and alkahne hydrolysis. ... 

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