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25.1.2.2.1 Variation 1: Oxidation with Metal Salts in High Oxidation States

DOI: 10.1055/sos-SD-025-00010

Podlech, J.Science of Synthesis, (20072528.

Various metal salts in high oxidation states have been recommended as oxidants for the conversion of primary alcohols into aldehydes without causing significant overoxidation to carboxylic acids.[‌2‌] In the past, the most frequently used reagents were chromium(VI) compounds, such as pyridinium chlorochromate, pyridinium dichromate, and chromium(VI) oxidebis(pyridine) complex and their utilization for the preparation of aldehydes from alcohols has been repeatedly surveyed.[‌3‌,‌25‌,‌26‌] While these are still very effective reagents, they are now usually avoided because of their toxicity and have been replaced by other similarly effective but less harmful reagents. In contrast, tetrapropylammonium perruthenate remains to be a most useful reagent for achieving this transformation, particularly in natural product synthesis, the benchmark for every reagent presented to the chemical community.

Mee eeeeeeeeeee ee eeeeeeee eeeeeeee eee eee eeeeeeeeeee ee eeeeeeeee eee eeee eeeeeeeeee eeeeeeee.[‌8‌,‌88‌,‌88‌] Meeeeeeeee eeeeeeeeeeeeee (Meeee'e eeeeeee[‌88‌]) eeeeee eeee eeeee ee eee eeeeeeeeeeeee eee eee eeeeeeeeee ee e eeeeee ee eeeeeeee eeee eeeeeeeee 8 ee eeeee ee Meeeee 8. Me eeeeeeee, eee eeeeeeeee ee eeeeee-8,8-eeee (8) ee eeee eeeeeeeeee (8) ee eeeeeeeeeee ee Meeeee 8.[‌88‌] Mee eeeeeee ee e eeeeee eee eeeeeeee-eeeeeeeee, eeeeeeeeeeee eeeeeeeee, eeeeee-eeeeee eeeee eeee ee eeee eee eeee ee eeeeeee. Me eeeee eeeee eeeeee eeeeee eeee Meeeeee' eeeeeee (eeee eeeee) eee, eeeee ee ee eeeeeeee eeeeee, eee eeeeeeeee eee ee eeeeeeee ee eee eeeeeeee ee eeeeee eeeeeee. Meeeeee eee eeee eeee 8.8 eeeeeeeeeee ee eeeeeeeee eee e eeeee eeeeeeeeeeeeee ee eee eeeeeee eeee eee eeeeeeee eeee eeeee eeeee eeeeee 8 ee 8 eeeee. Mee eeeeeee ee eeeeeeee eeee ee e eeeeeeeeee ee eeeeeeeeeeeeeee. Meeeee eee eeeeeee ee eeeeeeeeee ee eeeee eeeeeee[‌88‌] eee eee eeee eeeeee eee ee e eeeeeee-eeeeeeeee eeeeeee [e.e., eeee(eeeeeeeeeeeeeee eeeeeeeeeeeeee)] eee ee eeeeeeeeeeee.[‌88‌] Meeeeeeeee eeeeeeeeeeeeee eeeeeeee ee eeeeeee eeee eeeee ee eeee eeeeee ee eeeeeeeee eee e eeeeeeeeee eeeeee.[‌88‌] Meeeeee eee eeeeeeee ee eeeeeeeeee eeee eeeeeeeeee eeeeeeeeeeeeee eeee eeee eeeeeeee.[‌88‌‌88‌] Mee ee eeeee eeeeeeee ee eee eeeeeeee ee eeeeee eeee ee eeeeeeeeee eeeeeeeeeeeeee ee eeeeeeeeee eee eeeeeeee eee eeeeeeee eee 8 eeeeeee eeeeee eee eeeeeee ee eeeee.[‌88‌] Meeeeeeeee eee eeeeeeeee ee eee eeeeeeee ee eeeeeeeee eeeeee (8Å) ee eeeeeeeee eeeeeeeee.[‌88‌‌88‌] M eeeee eeeeeeeee ee eeeee eeeeeee ee eeee eeeeeeeeee eeee eeeeeeeeee eeeeeeeeeeeeee eee ee eee ee e eeeee eeeee, eeee eeeeee, ee ee eee eeee eeee eee eeeee-eeeee-eeeeeeeeee eeeeeeee, eeeeeeeeeeeee ee eee eeeeeee eeee eeeee eeeee eeeee eee eeeeeeeeeeeee eeeeeeee eeeeeeeeee eeee eee eeeeeeee ee eee eeeee eeeeeee eee eeeeeeeee.

Meeeee 8 Meeeeeeee ee Meeeeee Meeeeeee eeee Meeeeeeeee Meeeeeeeeeeeee[‌88‌,‌88‌,‌88‌,‌88‌]

Meeeeeeeeee 8

M8 Meeeeeeeee Meeee (%) Mee
MM8Me8, 8-Å eeeeeeeee eeeeee, 8e, ee 88 [‌88‌]
(MM8)8Me MM8Me8, ee 88 [‌88‌]
(MM8)8Me MMMe8, 8e, ee 88 [‌88‌]
(MM8)8Me MMMe8, MeMM, 8e, ee 88 [‌88‌]
(MM8)8Me MM8Me8, ee 88 [‌88‌]
MM(Me)Me MMM/eeeeeee 88 [‌88‌]
MeMMe, MM8Me8, 8e, ee 88 [‌88‌]
MMM/eeeeeee 88 [‌88‌]

Meeeee 8 Meeeeeeee ee Meeeee-8,8-eeee[‌88‌]

Meeeeeeeee eeeeeeeeee ee e eeeee-eeeeee, eeeeeeeeeeee eeeeeeeee, eeeeee eeeeee eeeee eeee eee ee eeeeee eee eeeeee eeeeeeee eee eeeeeee.[‌8‌,‌88‌] Mee eeeeee ee eee eeeeeee ee eeeeeee ee eeeeeeeeee eeee eee eeeeeeeeee eeeeeeeeee; eee eeeeeee, ee eeeeeeeeeeeeeeeee eee eeeeeeeee ee eeeeeeeee eeeeeee eeeeeeee eeee eeeeeeeeee eeeeeeeeee eeeeee eeeeeeeeee eeeee. Meeeeee, eeee eeeeeee ee eeee eeeeee eee eeee eeeeeeeee eeee eeee ee eeeeeeeeeeeeeee, eeeeeeeeee eee eeeeeeeeeeeee eeeeeeeee ee eeee eeeeee. Me eeeeeeeeee eeeeeeeeee ee eeee eeeeee eeee eeeeeeeeee eeeeeeeeeeeeee ee eee ee eeee eee eee eeeeeeeee ee eeee-eeeeeeeee eeeeeeeee. Mee eeeeeee, [8-(eeeeeeeeee-8M-eeeee-8-eeeee)eeeeeeeeeee]eeeeeeee (8) eee ee eeeeeeee ee eee eeeeeeeeeeeee eeeeeeee 88 ee 88% eeeee (88% ee eee eeeeeeee eeeeeeee 8 eee eeeeeeeee) (Meeeee 8). Meeeeee, eeeee eee Meeee eeeeee (eeeeeeee eeeeeeeee/eeeeee eeeeeeee/eeeeeeeeeeeee) eee eeeee eee eeee eeeeeeeee ee 88%.[‌88‌]

Meeeee 8 Meeeeeeee ee [8-(Meeeeeeeee-8M-eeeee-8-eeeee)eeeeeeeeeee]eeeeeeee[‌88‌]

Meeeeee eeeeeeee ee eee eee ee eeeeeeeeee eeeeeeeeee ee eee eeeeeeeee ee eeeeeee eeeeeeee eee eeeeeeeee ee Meeeee 8.[‌88‌,‌88‌] Me ee eeee e eeeeeeee eeeeeee eee eeeee-eeeee eeeeeeeee.

Meeeee 8 Meeeeeeee ee Meeeeee Meeeeeee eeee Meeeeeeeee Meeeeeeeee[‌88‌,‌88‌]

Meeeeeeeeee 8

M8 Meeee (%) Mee
(MM8)8Me 88 [‌88‌]
88 [‌88‌]
88 [‌88‌]

Meeeeeeeee eeeeeeeeee ee eeee eeee ee e eeeeeee eeee eeeeee eeeeeeeee (eeeeeee e eeeeeee eeeeeee)[‌88‌] ee ee eeeeeeeeeee eeee eeeeeeeeeeeeeeeeeeeee.[‌88‌] Meeeeee, eeee eee ee ee eeeee eeee eeeee eeeeeeeee eee eeeeeeeee eee eeee ee eeeeeeee eeeeeeeeee. M eeeeeeeee eeeeeee ee eeee eeeeeeeee eeee eeeeeeeeee eeeeeeeeee ee eee eeeeeeee ee eee(eeeeeeeeeeeeee) eeeeeeee.[‌88‌]

Meeeeeee(MM) eeeeeeee(eeeeeeee) eeeeeee (Meeeeee' eeeeeee[‌88‌]) ee e eeeeee eeeeee, eee eeeeeeeeeee eeeeeee eeee ee eeee ee e eeee- ee eeeeeee eeeeee ee eeeeeee eee eeeee eeeeeeeee ee eeeeeeee ee eeeeeeeee 88 (Meeeee 8).[‌88‌‌88‌] Meeeeee ee eee eeee ee eee ee eeeeee eee eeeee eeeeeee (eee eeeee), eeee eeeeeee ee eee eeee eeee eeee eeeee eeeeeee eeee. Meeeeee' eeeeeee ee eeee eeee ee eeeeeeeeeeeeeee, eee eeeeeee eeeeeee eeee ee eeeee eeeeee eee eeeeeeeeeee ee eee eeeeeee, eeeee eeeeee ee eeeeeeee(MM) eeeee eee eeeeeeee ee eeeeee eeeeeeeeee. Meeeee, eeeeeeee(MM) eeeee eeeeee ee eeeee ee eeeeeeeee eeeeeeee ee eeee e eeee eeee eee eeeeeeeeeee eeeee eeeeeee 88°M.[‌88‌]

Meeeee 8 Meeeeeeee ee Meeeeee Meeeeeee eeee Meeeeee' ee e Meeeeee Meeeeee[‌88‌‌88‌,‌88‌]

Meeeeeeeeee 8

M8 Meeeee Meeee (%) Mee
M 88 [‌88‌]
(MM8)8Me M 88 [‌88‌]
M 88 [‌88‌]
(MM8)8Me M 88 [‌88‌]

M eeeeeeeee eeee e eeeeeee ee eeeeeeee(MM) eeeee eeee 8,8-eeeeeeeeeeeeeeee (MMM), eeeee 8.8 eeeeeeeeeee ee eee eeeeeee ee eeee ee e eeee eee eeeeeeee ee eeeeeeeeeeeeeee ee eeee eeeeeeeeeee. Meee eeeeee eee eeeeeeee eeee eeee eeeeeee; eee eeeeeee, eeeee-8-ee eeeeeee eeeeeee ee 88% eeeee (Meeeee 8).[‌88‌]

Meeeee eee eeeeeeeeeee eee eeeee eeee eeeeee eeeeeee e eeeee eeeeeeeeeee, ee ee eee eeeeeeeee ee e eeeeeee eeeeeee, eeeeeee eeee eeeeeeee ee eeeeee eee eee eeeee ee ee e eeeeee eeeeeee ee eeeeeee eeeee. Meeeeeeee, eeeee-8-ee, 8-eeeeeeeeeeee-8-ee, eee eeeeeeeeee-8-ee eeee eeee eeeeeeee ee eee eeeeeeeeeeeee eeeeeeeee eeeee eeee eeeeee, ee 88, 88, eee 88% eeeeee, eeeeeeeeeeee.[‌88‌]

M eeeeee eeee eeeeeeeee eeeeeeeee eeee eeeeeeee eeeeeeee eeee eeeeeeeee 88 eeeeeeee eeeeeeeee eeeeeee ee eeeeeeeeeeeeeeeeeee eeeeeeeeeeee (MMMM, Mee'e eeeeeee[‌88‌]) eee 8-eeeeeeeeeeeeeeee M-eeeee ee e eeeeeeeeeeeeee ee-eeeeeee; eeee eeeeee eee ee eeeeeeeeeeee eeee ee eeeeeee eeeeeeee (eee Meeeee 8).[‌88‌‌88‌] Meeeee, eeee eeeeeeee eeeeee ee ee e eeeeee eeeeeeeeeee ee eeeee eeeeeeee eeeeeeeeee eeee ee eee Meeee eeeeee. Meeeeeeeeeeeeeeeeee eeeeeeeeeeee ee e eeeeeeeeeeee eeeeeeeee, eee-eeeeee, eeeeeeeeeee eeeeeeee, eeeeeee ee eeee eeeeeee eeeeeeee; ee ee eeeeeeee eee eee eeeeeeeee ee eeeeeee eee eeeeeeeee eeeeeeee eeeeeeee eeeeeeeee eee eeeeeee, eeeeeeeeeeee. Me eee ee eeee eee eeee eeeee eeeeeeeee eeeeeeeeee (eeee ee 8ee), eeeee eee eeee ee eeeeee ee eee Meeee eeeeeeee, ee eeee ee eee eeeeee eeeeeee (ee ee ee eeeee 8ee[‌88‌]). Meeeeee eeeeeeee eeee e eeeeeeeeeeee ee eee β-eeeeeeee eee eeeeeee eeeeeeee ee α-eeeeee eeeeeeeee eeeeeee eeeeeeeeeeee ee eeeeeeeeeeeee. Meeeeeeee, eeeeeeeee eeee eeeeeeeeeeeeeeeeeee eeeeeeeeeeee eeeee ee eeeeeeee eeeeeeeee ee eeeeee eeee eee ee eeeee ee eeee ee eeee eee Meeee eeeeee. Meeeeeeeeeee, e eee eeeeeeee eee eeeeeeee, eeee ee eee eeeeeeeee eeeeeeeee ee 8-(8-eeeee)eeeeeee ee 8-(eeeeeeeeeeeeee)eeeeeeeeeeeee, eee eeee ee eee eeeeeeee eeee eeee eeee eeeeeeee ee eeee, eeee eeee eeeee Meeee eeeeeeeeee.[‌88‌] Meeeeeeeeeeeeeeeeee eeeeeeeeeeee eeeeeeeee eeeeeeeee eee eeeeeeee ee eeeeeee, eeeeeee, eeeeeee, eeeee eeeeeee, eeeeeeee, eeeeeeeeeeeee, eeeeeee, eeeee eeeeee, eeeeeeeee, eeeeee, eeeeeeee, eeeeee, eeeeeeee, eeeeeee, eee eeeeeeee, eeeeeeee eeeeeee eeeee eee eeeeeee.

Meeeee 8 Meeeeeeee ee Meeeeee Meeeeeee eeee Meeeeeeeeeeeeeeeeee Meeeeeeeeeee/8-Meeeeeeeeeeeeeee M-Meeee[‌88‌‌88‌,‌88‌,‌88‌]

Meeeeeeeeee 8

M8 Meeeeeeeee Meeee (%) Mee
Me MM8Me8, 8e 88 [‌88‌,‌88‌]
(MM8)8MM=MM8 MM8Me8, 8e 88 [‌88‌,‌88‌]
MM8Me8, 8e 88e [‌88‌,‌88‌]
MM8Me8, eeeeeeee 8-Å eeeeeeeee eeeeee, 8.8e 88 [‌88‌]
MeMM, 8.8e 88e [‌88‌,‌88‌]
(MM8)8MMe MeMM, 8.8e 88 [‌88‌]
MM8Me8 88 [‌88‌]
eeeeeee-eeeeeeeee eeeeeee, eeeeeee, 88°M, 8e 88 [‌88‌]

e 88% eeeee eee Meeee eeeeee.

e 88% eeeee eee Meeee eeeeee.

Me eeeeeee ee eee eeeeeeeee ee ee eeeeeeeeeee eeee ee eeeee ee Meeeee 88; ee eeeee eee eeeeeeeeeeeee eeeeeeeeee ee 88% eeeee, eeeeeeee ee 88% eeeee ee eeeeeeeeee eeee eee Meeee eeeeeeeee.[‌88‌,‌88‌]

Meeeee 88 Meeeeeeee ee e Meee Meeee Meeeeeeeeeeeeeeeeee Meeeeeeeeeee[‌88‌,‌88‌]

Meee eeeeeeeeee eee eeeeeee eeeeeeeee eeee eeeeeeeee eeeeeee ee eeeeeeeeeeeeeeeeeee eeeeeeeeeeee (8eee%) eee eeeeee 8-eeeeeeeeeeeeeeee M-eeeee (8.8 eeeee). Meeeeeeeeeeeeee eee eeeeeeeeeeee eee eeee eeeeeeee ee eeeeeeee. Mee eeeeeeee eeeeeeeeee, eee eeeeeeee eeeeeeeeeeee ee eeeee eeeeeee ee eeeeeeeeeeee (88%) ee eeeeeeeeeeeeeee eeee eeeeeeee eeeeeee. Mee eeeeeeee ee eeeeeeee eeeeeeeee eeeeee (8Å) eeeeeeee eeeeeeee eeeee eee eee eeeeeeeeee ee eee eeeeeeeee. Mee ee-eeeeeee, 8-eeeeeeeeeeeeeeee M-eeeee, eeeeeeee eeee ee eeeeeeee ee eeeee eeeeeeee eee eeeeeeeeeeeeeee eeeeeeee eeee eeeeeeeee eeeeeeeee eeeeeee.[‌88‌] Meeee-eeeee eeeeeeeee eeeeee ee eeeeeeeee eeeeeeeee ee eeeeeee, eee eee eeeeeeee eeeeee ee eeeee ee eeeee eeeeeeee. Meee eeeee eeeeeeeeee ee e eeeeeeee eeeeeeee eeeeeeee eee ee ee eeeeeeee eeeeeeeeeeeeeeeeeee eeeeeeeeeeee eee ee eeee eeee eeeeeeeeeee ee e eeeeeeeeeeeeee eeeeeee; ee eeee eeee eee eeeeeeee eeeeee ee eeeeeeeee ee eee eeeeeeeeeeee (e.e., ee 8°M). Meeeeee eee eeeeeeee eeeeeee eeeeeee e eeeee eee ee eeeeee eee ee e eeeeeeeeee eeeeee eeeeeeeee; eee eee ee e eeeeeee-eeeeeeeee eeeeeeeeeeeeeeeeeee eeeeeeeeeeee eeeeeee eeeeeee eeee eeeeeeeeeee, eeeeeee, eee eeeeee eeeeeeee eee eeeeeeee eeeee ee eeee eeeeeeeee.[‌88‌,‌88‌]

8,8,8,8-Meeeeeeeeeeeeeeeeeee-8-eeee (MMMMM) ee eee eeeeeeee ee eeeeeeeee eeeeeee ee eeeeeeeeeeee(eeeeeeeeeeeeeeeeee)eeeeeeeee eee eeee ee eeee eee eee eeeeeeeee ee eeeeeee eeeeeeee eeeeeeee eeeeeeeee ee eeee eeeeee.[‌88‌] Meeeeeeeeeeee, eee ee (eeeeeeeeeeeee)eeeeeee ee eeeeeeeeeeeee ee eeeeeeeeeee eeee eee eeee eeeeeeee ee eeee eeeeeeee, eee eeee eeeeeeeeeeeee eeeeeee eeeeeeeeeeeee ee eee eeeeeeeeee eeee ee eeeeeeee, eee eeee eeeeeeee ee eeeeeee eeeeeeeee eeeeeeeeee eee eeeeeeeeeee eeee eeeeeeee ee eeeee eeeeeee.[‌88‌] Meeeeee eeeeeeeeeee ee eee eeeeeeeeeee ee 8,8,8,8-eeeeeeeeeeeeeeeeeeee-8-eeee ee eeeeeeeeeee eeee eeeeeee eeeeeeeee eee ee-eeeeeeee ee eeeeeeee ee Meeeeeee 88.8.8.8.8 eee 88.8.8.8.8.

Meeeeeeeeeee Meeeeeeee

Meeeeeeee 8; Meeeeee Meeeeeeee Meeee Meeeeeeeee Meeeeeeeeeeeee:[‌88‌]

Mee eeeeeee (8eeee) eee eeeee ee e eeee-eeeeeee eeeeeee ee MMM (8eeee) ee eeeeeeee, eeeee MMMe8 (88eM) ee ee. Meeee eee eeeeeeeeee ee eee eeeeeeee (MMM), Me8M eee eeeee ee eee eeeeeee eee eee eeeeeeee eee eeeeeeee ee eeeeeeeeeeeeee [eeeeee eee (eeeee e 8×88ee eeeeee), Me8M].

8-(Meeeeeeeee-8M-eeeee-8-eeeee)eeeeeeeeeeeeeeeeeeeeeeee (88); Meeeeee Meeeeeeee:[‌88‌]

MMMMMMM: Meeeeeeeeee eeeeee! Meeeeeeeee eeee eeeeeeee eeeeee eee eeeeeeeeeee ee eeeeeeeeee eeeeeeeeee.

M eeeeeee ee [8-(eeeeeeeeee-8M-eeeee-8-eeeee)eeeeeeeeeee]eeeeeeee (8; 8.88e, 8.88eeee) eee MMM (8e, 8.8 eeeee) ee MM8Me8 (8eM) eee eeeeeee ee ee eee 88e. M eeeeeee eeeeeee ee MMM (8e, 8 eeeee) ee MM8Me8 (8eM) eee eeeee eee eee eeeeeee eee eeeeeee eee ee eeeeeeeeee 88e, eeeeeee eeee Me8M (888eM), eeeeeeee, eee eeeeeeeeeeee ee eeeee e eeeeeee ee eee eeeeeeee eeeeeeee (88%) eee eee eeeee eeeeeeee; eeeee: 8.88e (88%).

Meeeeeeee 88; Meeeeee Meeeeeeee Meeee Meeeeeee(MM) MeeeeMee(eeeeeeee) Meeeeee:[‌88‌]

MMMMMMM: Meeeeeee(MM) eeeee eeee eeeeeeeee eee eeeeeeeeeee eeeeee eee ee eeeeeeeeee ee e eeeee eeeeeeeeee.

MeM8 (8.88e, 88eeee) eee eeeee eeee eeeeee ee e eeeeeee eeee ee eeeeeeee (8.88e, 888eeee) eee MM8Me8 (888eM) eeeeee eeee eee eeeeeeeeeee ee eee eeeeeee eee eee eeeeee 88°M.[‌88‌] Mee eeeee eee eeeeeeeee eeee e eeeeee eeee eeeeeeeeee Meeeeeee eee eee eeee eee eeeeeee eee 88eee ee ee. Mee eeeeeee (88eeee) ee e eeeee eeeeee ee MM8Me8 eee eeeee ee eee eeeeeee eeeeeee eee eeeeeeeee eeeeeeeeee ee e eeeee eee. Meeee eeeeeee eeeeeeee eee 88eee ee ee, eee eeee eee eeeeeeee eeee eee eeeeeee, eeeee eee eeeeee eeee Me8M (888eM). Mee eeeeeeee eeeeeee eeeeee eeee eeeeee eeeeeeeeeeee eeee 8% ee MeMM (8×888eM), 8% ee MMe (888eM), 8% ee MeMMM8 (888eM), eee eeeee (888eM), eeeee (MeMM8), eee eeeeeeeeeeee eeeee eeeeeee eeeeeeee ee eeeee eee eeeeeeee.

Meeeeeeee 88; Meeeeee Meeeeeeee Meeee Meeeeeeeeeeeeeeeeee Meeeeeeeeeee/8-Meeeeeeeeeeeeeee M-Meeee:[‌88‌]

Meeee MMMM (8eee%) eee eeeee ee eee eeeeeee ee e eeeeeee eeeeeee ee eee eeeeeee (8 eeeee), MMM (8.8 eeeee), eee eeeeeeee 8-Å eeeeeeeee eeeeee (888ee·eeee8) ee MM8Me8 (8eM·eeee8) eeee eee eeeeeeeeee ee ee eeeee eeeee. Me eeeeeeeeee ee eee eeeeeeee, eee eeeeeee eee eeeeeeee eeeeeee e eeeee eee ee eeeeee eee (eeeeeee eeee MM8Me8 ee MeMMe eeeeeeeee ee eee eeeeeee eeeeeeee eeeeeeee). Mee eeeeeeee eee eeeeeeeeee eee eee eeeeeee eee eeeeeeee ee eeeeee eee eeeeeeee eeeeeeee. Mee eeeeeeeee eee eee eeee eeee MeMM eee eeee ee eee eeeeeee, eeeeee eeee ee eee eeeeeeeee ee eeeeee eee MeMM ee eeeeeeeeeee eee ee eeeeeeee eee eeeeeee ee MM8Me8 eeeee ee eeeeeeeeee eeeeeee eeeeee eee.

References