Tert-butylamine, production

Preparation of w-Phenyl-tert-Butylamine 24 grams of the urea derivative obtained as indicated above, were well mixed with 96 grams of calcium hydroxide in a flask immersed in an air bath and provided with a dropping funnel the stem of which reached the bottom of the flask. The mixture was heated to 240°-260°C (inside temperature) for 7 hours during which time 86 cc of water was slowly added. The vapors were collected in a receiver cooled with ice. After extraction with ether and distillation, the product was obtained as a colorless liquid boiling from 80°-84 C at 9 mm according to U.S. Patent 2,590,079. 

In one of the early crucial experiments towards unravelling the reaction pathways observed, Shaw has elegantly demonstrated that in the case of ethyl and tert-butylamine reactions with N3P3CI6 the incoming nucleophile determines the type of product formed [18,53] (Eqs. 14-17)... 

Similarly, zeolites can catalyze the addition of ammonia to an olefinic double bond, as is exemplified by the BASF process for the production of tert-butylamine by reaction of isobutene with ammonia, in the vapor phase, over a rare earth exchanged ZSM-5 or Yzeolite (Fig. 2.20) [58, 59]. This process has an atom efficiency of 100% and replaced a conventional synthesis via a Ritter reaction, which employs HCN and sulfuric acid and generates formate as a coproduct. 

The stereochemistry of the cyclohexene adduct was established as cis by comparison of the product with the authentic tnms-isomcr prepared by ring opening of cyclohexene oxide with tert-butylamine. Similarly, the products obtained from (Z)- and ( )-l-deuterio-l-decene were converted to diastereomeric oxazolidinones which were compared with the authentic diastereo-mers. Furthermore, different diastereomers were obtained from ( )- and (Z)-l-phenylpropene, It is therefore reasonable to assume complete syn addition for all alkenes. 

A different problem occurs with 7-methylguanosine. The purine base of this nucleoside is hydrolyzed at basic pH, and very significant degradation occurs in an hour at pH 9.5 at room temperature. The mixture of oxidized nucleoside and protein, therefore, is kept at pH 9.1 and at 0-4°, at which only very limited hydrolysis of the base occurs in 1 hr. A different reducing agent, tert-butylamine borane (Aldrich Chemical Co.), is used the reduction is done for only 30-60 min at 4°, and the product is separated from free nucleoside on a Sephadex G-25 column at 4°. The nucleotide of the 7-methylguanosine is more stable than the nucleoside, and it also has been used to induce antibody to the 7-methylguanine structure. ... 

The intermediacy of phosphonoamidic-sulfonic anhydride (476) in the rearrangement of O-sulfonyl-N-phosphinoylhydroxylamine (477) with tert-butyla-mine was confirmed. The observed products, phosphonoamidate anion (478) and phosphonic diamide (479) correspond to attack of tert-butylamine at sulphur and phosphorus atoms of the anhydride (Scheme 110). ... 

D. tert.-Butylamine. To ISO ml. of cold 40% solution of sodium hydroxide is added 109.5 g. (1 mole) of ferL-butylamine hydrochloride with stirring. The solution is saturated with potassium carbonate (about 100-150 g.) the layer of amine is separated and dried over 20 g. of sodium hydroxide pellets. The product is distilled using an ice-cooled receiver, and the fraction boiling at 44—46° is collected. If the purified amine hydrochloride is the starting material for this step the yield ranges from 65 g. to 69 g. (89-94%). When the crude amine salt is employed, the yield is 46-60 g. (64-83%) (Note 9). 

Sodium bis-(2-methoxyethoxy)aluminium hydride (ref. 84) and lithium tri-tert-butoxyaluminium hydride (ref. 85) showed excellent stereoselectivity for podophyllotoxin compared with other reagents. However, these reagents have the disadvantage that low temperature (-75 C) is required to obtain satisfactory yield. Although the stereoselectivity was inferior to that of the above-mentioned aluminium hydride complexes, borane-terf-butylamine complex (ref. 86) and borane ammonia complex (ref. 87) gave the products in more than 90% yield. The reactions proceeded at room temperature, and borane-tert-butylamine complex did not require the use of a nitrogen stream. 

The production of tert-hutylamine is interesting for the fact that this amine has been used to demonstrate the technical potential of hydroamination in commercial amine production [route (b) in Topic 5.3.4]. BASF introduced in the early 1990s the first process that operates vith a zeolite catalyst and converts isobutene directly with ammonia. The reaction is carried out by contacting the supercritical reaction mixture with the catalyst at temperatures between 250 and 300 °C and at pressures between 200 and 350 bar. Under equilibrium conversion conditions tert-butylamine forms in 95% selectivity. 

The current experiment involves the preparation of the sterically hindered amine A -ferf-butyl-3,5-dimethylaniline. Other preparations of this amine involve addition of methyllithium to lV-3,5-dimethylphenylacetone imine and the reaction of l-bromo-2,4-dimethylbenzene with terf-butylamine either via aryne formation or by palladium-catalyzed alkylation. The current method, the reaction of tert-butylamine with the 2,4,6-trimethylpyrylium cation, involves inexpensive starting materials and proceeds in high yield. The molybdenum(III) complex of the deprotonated form of this amine, Mo[N(f-Bu)(3,5-C6H3Me2)]3, splits the N=N triple bond in N2 to afford molybdenum(VI) nitrido products. This latter reaction is the key step in the recently discovered catalytic process to convert N2 to ammonia under ambient conditions. 

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