R-Butyl nitrite

Hexfluorophosphate salts behave similarly.108 The diazonium tetrafluoroborates can be prepared either by precipitation from an aqueous solution by fluoroboric acid109 or by anhydrous diazotization in ether, THF, or acetonitrile using r-butyl nitrite and boron trifluoride.110 Somewhat milder reaction conditions can be achieved by reaction of aryl diazo sulfide adducts with pyridine-HF in the presence of AgF or AgNQ3. 

Isolation of the intermediate diazonium salt can be avoided in many cases. Treatment with r-butyl nitrite followed by CuBr2 can give oxidative bromination in addition to replacement of the diazo group... 

Adde peptide synthesis. Hofmann el aV used the Rudii er modification of the azide synthesis (see n-Butyl nitrite) except that they used r-butyl nitrite and hydrogen chloride in dimethylformamide. Comparison with the standard azide procedure showed the modified procedure to be superior in yield and in ease of operation. 

Other leaving groups are effective in the oxidative addition with Pd°, and can lead to efficient Heck reactions. An attractive possibility is an aniline as starting material, with in situ generation of a diazonium salt. While the oxidation of the amino group can occur with Pd alone at elevated temperatures, deliberate addition of r-butyl nitrite leads to... 

McMillan (1962) photolyzed r-butyl nitrite at 253.7 and 313.0 nm and found that acetone was the major product, with CH3ONO2 and N2 as minor products. He noticed that the acetone quantum yield decreased with increasing pressure. Therefcne he interpreted the acetone as coming from decomposition of an excited r-butoxyl radical, which could be stabilized by collision. Thus the primary process is... 

A one-pot protocol to obtain triazoles from aromatic amines has been reported. The aryl azides, generated in situ from the corresponding amine with r-butyl nitrite and TMSNs, participate in Cu(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition giving l,4-disubstituted-l,2,3-triazoles 244 (Scheme 3.35). 

Azide 367 is prepared from 4-r -butyl-2-nitroaniline in 76% yield by its diazotization followed by treatment with sodium azide. In a 1,3-dipolar cycloaddition with cyanoacetamide, azide 367 is converted to triazole 368 that without separation is directly subjected to Dimroth rearrangement to give derivative 369 in 46% yield. Reduction of the nitro group provides ortfc-phenylenediamine 371 in 91% yield <2000EJM715>. Cyclocondensation of diamine 371 with phosgene furnishes benzimidazol-2-one 370 in 39% yield, whereas its reaction with sodium nitrite in 18% HC1 leads to benzotriazole derivative 372, which is isolated in 66% yield (Scheme 59). Products 370 and 372 exhibit potassium channel activating ability <2001FA841>. 

As indicated above, tertiary aromatic amines are directly C-nitrosated. The usual reagents are sodium nitrite and dilute hydrochloric acid, sodium nitrite and glacial acetic acid containing concentrated hydrochloric acid, and nitrite esters with hydrochloric acid [21a, 27]. While tertiary amines with such complex alkyl groups as found in A,A-di(3,5,5-trimethylhexyl)aniline are readily nitrosated [25], of the four A-butyl-A-methylaniline isomers, JV-r-butyl-A-methylaniline does not undergo the reaction, and even the nitroso compounds which did form were only unstable oils [27]. 

Lavi, R., Schwartz-Lavi, D., Bar, I. and Rosenwaks, S. (1987). Directional properties in photodissociation A probe for the symmetry and geometry of excited states of dimethylnitrosamine and ferf-butyl nitrite, J. Phys. Chem., 91, 5398-5402. 

Equations 4-8 illustrate some mild methods that can be used to cleave amides. Equations 4 and 5 indicate the conditions that were used by Woodward9 and Eschenmoser,10 respectively, in their synthesis of vitamin B,2- Butyl nitrite,11 nitrosyl chloride,12 and nitrosonium tetrafluoroborate (NO+BF4 )13 have also been used to cleave amides. Since only tertiary amides are cleaved by potassium r-butoxide (eq. 6), this method can be used to effect selective cleavage of tertiaiy amides in the presence of primary or secondary amides.14 (Esters, however, are cleaved by similar conditions.)15 Photolytic cleavage of nitro amides (eq. 7) is discussed in a review.16 n,o4/cci4 ... 

In one of the most elegant applications of gas-phase inhibition by nitric oxide, Birss, Danby and Hinshelwood have studied the thermal dissociation of r-butyl peroxide. The low temperatures required for pyrolysis permitted mass spectro-metric determination of t-butyl nitrite, and a fairly complete kinetic analysis of the system was possible. The rate of decomposition of peroxide was related to the consumption of nitric oxide and to the appearance of butyl nitrite during the inhibition period, and curves were obtained which showed the acetone and ethane concentrations as a function of time during and after inhibition. 

N203 passed into an ice-cooled soln. of tributylacetamide (prepn. s. 127) in glacial acetic acid, allowed to stand at room temp, overnight, and heated 2 hrs. on the steam bath — tributylacetic acid. Y 80%.— The reaction can also be performed with butyl nitrite. (N. Sperber, D. Papa, and E. Schwenk, Am. Soc. 70, 3091 (1948) s. a. F. J. Buckle, R. Heap, and B. C. Saunders, Soc. 1949, 912.)... 

Mc.Murrey and co-workers modified the reaction by carrying it out in a reductive medium of TiCla followed by hydrolysis and an oxidizing medium of O3 (92a] and (92b] respectively. Sec also Bartlett et al. (93 ]. They used r-butyl hydroperoxide in the presence of peniavalent vanadium salt as a catalyst, Korn-blum and Wade (94a] gave an unusual method of oxidation of secondary nitro-alkanes to ketones with nitrous esters and sodium nitrite at room temperature ... 

Christie and Hetherington (1977) photodecomposed r-butyl, isopropyl, and ethyl nitrites at 253.7 nm. They found respective values for of0.87,0.67, and 0.45. Their result agrees exacdy with that of McMillan (1962) for r-C4H9ONO, but is somewhat lower than the value 0.86 reported for 1-C3H7ONO (McMillan et al., 1971). 

Isobutyl nitrite Butyl alcohol scc-Butyl alcohol t r -Butyl alcohol Ethyl ether Isobutyl alcohol Ethyl sulfide Pyridine Isovaleraldehyde 3-Methyl 2-butanone Isobutyl formate Isopropyl acetate Methyl isobutyrate Isoamyl nitrite tert-Amyl alcohol Isoamyl alcohol... 

A soln. of the startg. bicyclic enolether and 72-butyl nitrite in 50%-ethanol treated with acetic acid or 10%-HCl product. Y almost 100%. - Any alkyl nitrite or even Na-nitrite may be used. F. e. s. J. R. Mahajan, G. A. L. Ferreira, and H. C. Araujo, Chem. Commun. 7972, 1078 N-acetyloximinolactams s. Synthesis 1973, 313. 

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