1-Bromopentane, 740 table

According to the coordinatoclathrate predict, the Spiro compound 23 will not allow the formation of inclusion compounds with dimethylformamide and other polar solvents, but with benzene, tetrahydrofuran, and 1-bromopentane (Table 3). Due to the limited number of guest inclusions, a lattice cavity of rather restricted dimensions is suggested for 23 e.g. toluene, cyclohexane or dioxane are not suitable guest partners for 23, whereas lower homologues (cf. benzene, tetrahydrofuran) are readily included 37). The behavior of a reduced analogue of 23, the hydroxymethyl — substituted spiro compound 24, is in some way comparable since an inclusion compound with benzene is the only one known interestingly it is formed exclusively with optically resolved but not with racemic 24 49). 

Table I. Reaction of 1-Bromopentane with Various Nucleophiles under PTC Conditions ...

TABLE 27. Reaction of PhO (3) with 1-bromopentane (1) under various phase-transfer catalytic (0.01) conditions (water 110°C)... 

Internal alkenes react less readily with RBeH. The reactivity of 1-pentene to EtHBe-n OEtj is >200 times that of 2-pentene the trialkylated ethene, 2-methylbut-2-ene, is inactive to addition of RBeH (R = Et, i-Bu) at 84°C and reacts only slowly with the more active, base-free i-BuBeH at 110°C (see Table 1) . Beryllium migrates to the end of the carbon chain as shown by the bromination of the products from 2-pentene and EtBeH 82% 1-bromopentane, 12% 2-bromopentane and 6% 3-bromopentane. ... 

Figure 4. First heating (A) and cooling (B) DSC traces of a,o)-di(hydroxyphenyl) PHMS-5 (sample 2, Table 2). Heating (D) and cooling (C) DSC traces of a,a)-dl-(pentoxy)PHMS-5, l.e., 1-bromopentane end capped a,o)-dl(hydroxyphenyl) PHMS-5 (sample 3, Table 2).

Therefore, if one molar equivalent of KI reacts with one molar equivalent of 2-bromopentane at a given rate, the identical reaction of one molar equivalent of 2-bromopentane with 10 molar equivalents of KI shordd have a rate that is 10 times greater. Table 11.1 reports relative rates rather than absolute values of k (the actual rate constant). Note that the relative rate is calculated by taking the rate of the bromomethane reaction as the standard (relative rate = 1) and all other rates are reported as their ratio relative to bromomethane. 

The ether is prepared via the corresponding halide. If the C-0 bond in 163 is disconnected, the logical bond polarization makes O 6- and a donor site Cj, and that of C2 is 6+, or (an acceptor site). In Chapter 25, Table 25.1 indicates that a synthetic equivalent for Cg is an alkyl halide. Therefore, a reasonable disconnection of 163 leads to 2-bromopentane (167) and the nucleophilic methoxide ion. This suggests a Williamson ether synthesis (Section 11.3.2). Can 167 be prepared directly from 1-pentene The answer is yes, by reaction of the alkene with HBr (Chapter 10, Section 10.2). Therefore, the retrosynthesis shown leads to the synthesis shown in which 1-pentene reacts with HBr to give 167, and a subsequent Sn2 reaction with... 

Chapter 1 Introduction, Record Keeping, and Laboratory Safety 15 Table 1.2 Table of Reactants and Products for Preparation of 2-Bromopentane... 

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