Portlandia albiflora Britton & Harris ex Standl. syn. Portlandia platantha Hooker - Rubiaceae

Shrub or small tree, 1-2m high, native to Jamaica (critically endangered; only one locality of limastone rocks and cliffs in St.Andrew), cultivated in Hawaii; leaves leathery, lush green, obovate-oblong or narrowly elliptic, narrowed at base; flowers trumpet-shaped, 10-12cm long, corolla white inside often tinged with pink outside.
[R.Kaiser, Scent of the Vanishing Flora, Zurich 2011, 75-76]
[Flora of Jamaica, containing descriptions of the flowering plants known from the island by Fawcett, William, 1851-; British Museum (Natural History). Dept. of Botany; Rendle, A. B. (Alfred Barton), 1865-1938 ]
https://archive.org/details/floraofjamaicaco07fawcuoft/page/18/mode/2up

„This flowers are wonderfully fragrant, perceived by humans as sensual as probably no other flower can offer, something like warm vanilla cream, also tender floral and very skinny. This olfactory and sensual delight is mainly due to the complex interaction of linalool, methyl salicylate, geraniol, (E)-geranylacetone, jasmone, anisaldehyde, (E)-2,3-dihydrofarnesal, (E)-nerolidol, (Z)-dec-7-eno-4-lactone (the so-called γ-jasminolactone), decano-5-lactone, (Z)-dec-7-eno-5-lactone (the so-called jasmine lactone), (E,E)-farnesol, 1H-indole, and benzyl salicylate.“ (Vanillin present in headspace: 0.03%)
[R.Kaiser, Scent of the Vanishing Flora, Zurich 2011, 76 and 409]

„Portlandia leaves do not have any particular fragrant or scent. However, when ground, they emanate a distinctive aroma.“ Main volatiles (HS-SPME-GC-MS) of grounded P.albiflora leaves were 3-methylbutanal (4.4%), 1-penten-3-one (12.3%), hexanal (7.9%), (E)-2-hexenal (30.0%), linalool (14.6%), and borneol (13.1%).
[Priestap, Horacio A., et al. „Volatile constituents of five species of Portlandia (Rubiaceae).“ Journal of Essential Oil Research 26.2 (2014): 125-129]

Portlandia albiflora (with more pictures) at toptropicals.com