Telomerization of butadiene with ammonia

In an analoguous case, two-phase telomerization of butadiene with ammonia to give octadienylamine has been reported where higher selectivity is realized in a two-phase system of water-toluene. Here, octadienylamine is more reactive than ammonia and consecutive reaction leads to sec and ten amines. By adopting a two-phase strategy, a primary amine selectivity as high as 91 % has been realized (Drieben-Hoscher and Keim, 1998). 

Bayer (1997) has claimed that in a water-CH2Cl2 system, using water soluble Pd(OAc)2 -triphenylphosphine trisulphonic acid catalyst, octa-2,7-dienyl-l-amine and octa 1,7-dienyl -3-amine can be obtained by telomerization of butadiene with ammonia. 

The simultaneous homogeneous telomerization of butadiene with ammonia catalyzed by Pd complexes (see also Section 2.7) normally leads to a mixture of mono-, di-, and trioctadienylamines [4]. Hydrogenation of the 2,7-octadienyl-amine yields commercially important n-octylamine (eqs. (3) and (4)). 

Although the telomerization of dienes in a two-phase system has been intensively investigated with compounds containing active hydrogen such as alcohols, amines, phenols, acids, etc., the selective and productive telomerization of butadiene continues to be a challenge. It is only recently that primary octadi-enylamines have been obtained with selectivity up to 88% in the telomerization of butadiene with ammonia using a two-phase toluene/water system and Pd(OAc)2/tppts as the catalyst [Eq. (23)] [125]. 

An interesting variant of entry 5 is entry 11, in which one of the educts is a polar and the other a nonpolar reactant yielding organic products. Once again the catalyst is in the aqueous phase and thus easily separated from the products. This technique is used in the telomerization of butadiene with water (Kuraray process cf. Section 6.7) and the telomerization of butadiene with ammonia (see Section 4.2.2). 

An interesting new example is the two-phase telomerization of butadiene with ammonia, yielding octadienylamines [57]. When this reaction is carried out in homogeneous one-phase solution, a great amount of primary, secondary and tertiary amines is formed [56]. With the two-phase techniques using water, and toluene or pentane as the second phase, the consecutive reactions (Eq. 2) can be almost completely avoided, and the primary octodienylamines are the only main products. This reaction has not yet been realized industrially. 

Driessen- HOlscher/ Univ. Paderborn Telomerization of butadiene with ammonia Pd Water [32-33]... 

In biphasic systems, one may often observe what may be called protection by phase separation . A splendid example of this phenomenon is the telomerization of butadiene with ammonia (Scheme 28). The straightforward products of this reaction are the primary octadienylamines which, however, are more reactive nucleophiles than NH3 itself As a result, the product mixture of such... 

Tsuji has described the preparation of long-chain amines by the palladium-catalysed telomerization of butadiene with ammonia, tertiary amines are formed, whereas nitroalkanes undergo replacement of the a-hydrogen atoms with octa-2,7-dienyl groups. Nickel(0) complexes catalyse a similar telomerization. ... 

Primary amines can be synthesized selectively by the catalytic two-phase telomerization of butadiene and ammonia [Eq. (12)], provided that the two amines are extracted from the aqueous catalyst phase with a polar solvent immediately after their synthesis (104). 

Telomerizations have been among the first reactions tested under biphasic conditions [45, 190], starting with butadiene and methanol on Pd/TPPMS catalysts and yielding l-methoxy-2,7-octadiene. The telomerization in the presence of water as reactant (hydrodimerization cf Scheme 1) has been commercialized [15, 31, 42-44]. These biphasic developments of the Kuraray Corporation yield 1-octanol or 1,9-nonanediol, respectively (cf [15, 31, 42 4, 86, 133, 137, 244 e] and Section 2.3.5). Similar developments (but without technical realization) have been described by BASF [134], Mitsubishi [135], and Shell [136], and others [215 d, 242, 268]. The telomerization of butadiene and ammonia may also be biphasic [243]. 

It may be noted that other homogeneous telomerization reactions of butadiene with ammonia lead to trioctadienylamines. When carried out in an aqueous two-phase operation with Pd/TPPTS, primary and secondary octadienylamines are obtained [4]. Telomerization of butadiene with formic acid or its salts using the above-mentioned process can produce 1,7-octadiene [5], Substituting isoprene for butadiene leads to dimethyloctadiene. The biphasic Pd-catalyzed telomerization of butadiene with carbohydrates in aqueous operation is also an important reaction and yields the desired ethers (Scheme 2) [6]. 

Telomerization Reactions. Butadiene can react readily with a number of chain-transfer agents to undergo telomerization reactions. The more often studied reagents are carbon dioxide (167—178), water (179—181), ammonia (182), alcohols (183—185), amines (186), acetic acid (187), water and CO2 (188), ammonia and CO2 (189), epoxide and CO2 (190), mercaptans (191), and other systems (171). These reactions have been widely studied and used in making unsaturated lactones, alcohols, amines, ethers, esters, and many other compounds. 

The most characteristic reaction of butadiene catalyzed by palladium catalysts is the dimerization with incorporation of various nucleophiles [Eq. (11)]. The main product of this telomerization reaction is the 8-substituted 1,6-octadiene, 17. Also, 3-substituted 1,7-octadiene, 18, is formed as a minor product. So far, the following nucleophiles are known to react with butadiene to form corresponding telomers water, carboxylic acids, primary and secondary alcohols, phenols, ammonia, primary and secondary amines, enamines, active methylene compounds activated by two electron-attracting groups, and nitroalkanes. Some of these nucleophiles are known to react oxidatively with simple olefins in the presence of Pd2+ salts. Carbon monoxide and hydrosilanes also take part in the telomerization. The telomerization reactions are surveyed based on the classification by the nucleophiles. 

---