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Alkylation and acylation of the alkenes 9b, c and 10a, b, which are easily prepared from the corresponding a-amino alcohols, with 2-halobenzyl and 2-halobenzoyl halides respectively, gives 11-15. These compounds cyclize with excellent diastereo-and regioselectivity to the enantiomerically pure N-heterocycles 18-20 in an intramolecular Heck reac-tion using 5 mol-% of Pd(OAc)2 in the presence of PPh3, TPAB and KOAc. Under the same conditions substrate 17 leads to the enantiomerically pure benzazepine 24. The reaction of the bromoarene derivatives 14-15 must be performed under high pressure to give good results.

Acylation of the alkenes la-d and 3, easily prepared from the corresponding a-amino acids, with 2-iodobenzoyl chloride gives 2a-d and 4 which cyclize to the enantiopure dihy-droisoquinolinones 5a-d and 9, resp., in an intramolecular Heck reaction using 5 mol-% of Pd(OAc), in the presence of PPh3, TPAB, and KOAc with excellent diastereoselectivity.

The iodoarenes 9 and 10, bearing (E)‐ and (Z)‐alkene moieties, respectively, easily prepared by alkylation of the corresponding alcohols 7a–c and 8a–c with 2 iodobenzyl iodide, undergo intramolecular Heck reactions to give the isochromanes 12–15a–c in good yields. The selectivity of the reaction depends on the size of the substituent R in 9 and 10; increasing bulkiness of R leads to a decrease in diastereoselectivity and an increase in regioselectivity. High‐pressure experiments confirm the proposed mechanism and show that bromoarenes such as 11, which tend to be unreactive at ambient pressure, give good results when the cyclisation is performed under high pressure.