Combination tables amines

A special case of combination of amine catalysis and solvent effect is givetf by the easy oxidation of aliphatic and aromatic thiols in tetra-methylguanidine which acts both as base and as a dipolar aprotic solvent (see Table 14). 

International Specialty Products (ISP) suppHes ethyl, isopropyl, and -butyl half-esters of PMVEMA as 50% solutions in ethanol or 2-propanol. Typical properties are shown in Table 8. These half-esters do not dissolve in water but are soluble in dilute aqueous alkaU and in aqueous alcohoHc amine solutions. The main appHcation for the half-esters is in hairsprays where they combine excellent hair-holding properties at high humidity without making the hair stiff or harsh. These half-esters are easily removed during shampooing, have a very low order of toxicity, and form tack-free films that exhibit good gloss, luster, and sheen (see Hair preparations). 

In order to produce high yields of ester in this manner it is necessary to remove the by-product ammonia (or amine) either by heating or combining with mineral acid, eg, H2SO4 or HCI. Recent work has shown that acidic ion-exchange resins can be used in place of mineral acids for converting sensitive unsubstituted amides (76). The stmctural relationships involved in esterification of amides are shown in Table 2 (77). 

Data given in Tables 1-6 clearly show a significant dependence of P2 and p4 on amine concentration, that is, at least one of the apparent rate constants kj contains a concentration factor. Thus, according to the mathematical considerations outlined in the Analysis of Data Paragraph, both p2, P4 exponents and the derived variables -(P2 + p)4> P2 P4 ind Z (see Eqns. 8-12) are the combinations of the apparent rate constants (kj). To characterize these dependences, derived variables -(p2+p)4, P2 P4 and Z (Eqns. 8,11 and 12) were correlated with the amine concentration using a non-linear regression program to find the best fit. Computation resulted in a linear dependence for -(p2 + p)4 and Z, that is... 

In general, cyclization can be expected in compounds having the potential for formation of five- or six-membered rings. In addition to the more typical bromination reagents, such as those listed in Table 4.2, the combination of trimethylsilyl bromide, a tertiary amine, and DMSO can effect bromolactonization. 

DTDMAC (Table 1.3) is produced at the industrial scale by combining a suitable amine with an alkylating agent. 

Alkanolamines, generally referred to as amines, are organic compounds of the form Hn-N-(R0H)3-n (3) the hydroxyl group generally provides for the compounds solubility in water, while the HN group provides the alkalinity in water solutions to cause the absorption of acid gases. Amine processes used commercially are shown in Table I. These compounds are chemical solvents they combine chemically with H2S, C02, and other sulfur compounds. They are customarily regenerated by the application of heat. 

The a-bromoamide (3 mmol), the amine (or its salt) (3.5 mmol) and TBA-Br (97 mg, 0.3 mmol) are added to a stirred two-phase system of aqueous NaOH (50%, 10 ml) and CHjClj (12 ml). Stirring is continued for a further 4-10 h (see Table 5.3). H20 (10 ml) is then added and the organic phase is separated and washed with H20 (3 x 50 ml) and HC1 (1M, 3 x 30 ml). The combined aqueous phases are neutralized with NaHC03 and extracted with CH2C12 (3 x 50 ml). The dried (MgS04) organic extracts are evaporated to yield the aminocarboxamide, which is purified by chromatography from silica. 

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