Tartaric acid derived host compound

Photocyclization of A -alkylfuran-2-carboxyanilides conducted in inclusion crystals with optically active tartaric acid-derived hosts led to the formation of tricyclic /ra r-dihydrofuran compounds with up to 99% ee <1996JOC6490, 1999JOC2096>. 2-(/>-Alkoxystyryl)furans underwent photocyclization to give 5-(3-oxo-(/ )-butenyl)benzo[ ]furans as the predominant isomers in undehydrated dichloromethane as shown in Equation (59). The intermediate alkyl enol ether could be obtained by performing the reaction in anhydrous benzene <1999OL1039>. 

Among the different types of compounds whose complexation properties have been studied are various amides linear oxoamide 9 [22], fumaramide 10 [23,24] and methanetricarboxamide 11 [25], biphenyl derivatives 12 [26], and derivatives of tartaric acid 13-16, that can also be prepared in an optically active form [27], The above-mentioned chiral hosts have been found to form inclusion complexes with chiral guests 17 and 18. Molecular recognition between chiral hosts and... 

Some amide derivatives have been reported to form inclusion complex with a wide variety of organic compounds.9 Optically active amide derivatives are expected to include one enantiomer of a racemic guest selectively. According to this idea, some amide derivatives of tartaric acid (11-13) were designed as chiral hosts.10 As will be described in the following section, these amide hosts were found to be useful for resolution of binaphthol (BNO) (14) and related compounds (15,16). 

Optical resolution of some hydrocarbonds and halogeno compounds by inclusion complexation with the chiral host (9a) has been accomplished.11,12 Preparation of optically active hydrocarbons is not easy and only a few example of the preparation of optically active hydrocarbons have been reported. For example, optically active 3-phenylcyclohexene has been derived from tartaric acid through eight synthetic steps.11 Although one-step synthesis of optically active 3-methylcyclohexene from 2-cyclo- hexanol by the Grignard reaction using chiral nickel complex as a catalyst has been reported, the enantiomeric purity of the product is low, 15.9%.11 In this section, much more fruitful results by our inclusion method are shown. 

Toda, F., Miyamoto, H., and Ohta, H. (1994) Efficient Optical Resolution of c7.s -4-Methylcyclohex-4-enc-l, 2-dicarboxylic Anhydride, c/.v-4-Methylcyclohex-4-ene-1,2-dicarboximide, and Their Derivatives by Complexaion with Optically Active Host Compounds Derived from Tartaric Acid, J. Chem. Soc., Perkin Trans 1. 1601-1604. 

Toda, F., Tanaka, K., and Okuda, T. (1995) Optical resolution of methyl phenyl and benzyl methyl sulfoxides and alkyl phenylsulfinates by complexation with chiral host compounds derived from tartaric acid, J. Chem. Soc., Chem. Commun. 1995, 639-640. 

Miyamoto, FL, Sakamoto, M., Yoshioka, K., Takaoka. R., and Toda, F. Resolution of hydrocarbons by inclusion complexation with a chiral host compound Tetrahedron Asymmetry 2000, 11, 3045-3048 Tanaka, K., Honke, S., Urbanczyk-Lipowska, Z., and Toda, F. New chiral hosts derived from dimeric tartaric acid Efficient optical resolution of aliphatic alcohols by inclusion complexation, Ear. J. Org. Chem. 2000,3171-3176. 

The enantioselective reduction of acylpyridines has been improved by the addition of trimethoxyborane to the oxazaborolidine reagent <97SL273, 97T12405>. An alkyl pyridyl sulfoxide is resolved by complexation with a chiral host compound derived from tartaric acid <97TA2505>. 

Carbohydrates or carbohydrate-derived compounds were used to promote asymmetric induction in the crystalline state. In particular, enantio-selective photocyclization of a-ketoamide 105 in the clathrate crystalline environment with chiral hosts 106 and 107 derived from tartaric acid provided the /9-lactam 108 with high enantiomeric purity (Scheme 28) [81]. 

The enantioselective Michael addition of mercapto compounds with an optically active host compound derived from 1 1 inclusion complex of 2-cyclohexenone with (-)-A derived from tartaric acid and a catalytic amount of benzyltrimethyl ammonium hydroxide on irradiation with ultrasound for 1 hr. at room temperature gave the adduct in 50-78% yield with ee 75-80% (Scheme 8). 

---