Science of Synthesis

de Meijere, A.; Kozhushkov, S. I., Science of Synthesis, (2009) 48, 558.

Cyclopropene itself and several substituted derivatives ‌255‌ undergo cyclooligomerization reactions, i.e. formal [2+2], [2+2+2], and [2+2+2+2] cycloadditions onto each other to form tri-, tetra-, and pentacyclic skeletons[‌6‌,‌364‌] (see also Houben–Weyl, Vol. E 17a, pp 140, 204, 222). The [2+2] cyclodimerization, which can be brought about by irradiation,[‌365‌–‌367‌] under Lewis acid catalysis,[‌368‌–‌373‌] thermally,[‌371‌,‌372‌,‌374‌,‌375‌] or under metal catalysis, affords tricyclo[3.1.0.02,4]hexanes ‌256‌. The first three versions of this transformation are summarized in ‌Table 9‌. The results indicate that, as a rule, the Lewis acid catalyzed cyclodimerizations are the most efficient ones. However, this is not so for every cyclopropene (cf. entries 7 and 9), as ring-opening reactions sometimes compete.[‌368‌] The best yields (virtually quantitative) of the parent exo-tricyclo[3.1.0.02,4]hexane and its dimethyl derivative are obtained upon treatment of cyclopropene (‌255‌, R1 = R2 = R3 = R4 = H) and 3-methylcyclopropene (‌255‌, R1 = R2 = R3 = H; R4 = Me), respectively, with zeolites (4-Å molecular sieves) (entries 5 and 6),[‌369‌,‌370‌] whereas 1,3,3-trisubstituted cyclopropenes do not cyclodimerize under these conditions. In several rare cases the appropriately substituted cyclopropenes undergo spontaneous thermal [2+2] dimerization to afford tricyclo[3.1.0.02,4]hexanes, but only in low yields (entries 10 and 11).

‌Meeee 8‌ [8+8] Meeeeeeeeeeeeeeee ee Meeeeeeeeeeee Meeeeeeee ee Meeeeeeeee, ee Meeee Meeee Meeeeeeee, ee Meeeeeeee[‌888‌–‌888‌]

e Meeeeee ee eee eeeeeeeeeeee (8:8).

e 8M-Meeeeeeeeee-8-eee ee e eeeeeeeeee.

e Meeeeeee ee “eeee”.

Meeeeeeeeeeeeeeee ee 8,8-eeeeeeeeeeeeeeeeeeee ‌888‌ eee eeee ee eeeeeee eeeee eeeee eeeeee eeeeeeeee, eee eeee eeee eeeeeeee eeeeeeeeee (‌Meeeee 88‌).[‌888‌,‌888‌,‌888‌] Me eee eeeee eeee, eee eeee eeeeeeeeeeee eeeeeeeee ee eeeeeeeee eeeeeeeee eeee ee eee(eeeeeeeeeeeeeeeeeeee)eeeeeeeee(8) ee eee(eeeeeeeee-8,8-eeeee)eeeeeeeee(8) ee eee eeeeeee ee eeeeeeeee eeeeeee eee eeee eeeeeeeee 8,8,8,8-eeeeeeeeee-eeeeeeeeeee eeeeeeee[8.8.8.88,8]eeeeeee ‌888‌ ee eeee eeeeee, eee eeee eeeee eee eeeeeeeeeeeee eeeeeeeeeeeeee, 8,8,8,8,8,8,88,88-eeeeeeeeeeeeeeeeeee[8.8.8.88,8.88,8.88,88]eeeeeeeee ‌888‌ ee eeeeeeeeee, eeeeee ee eee eeeeee (88–88%) (‌Meeeee 88‌).[‌888‌,‌888‌] Mee eeeeeeeee ‌888‌ eee eeeeee ee eeeeeeeee eeee eee eeee eeeeeeee ‌888‌.

‌Meeeee 88‌ Meeeee-Meeeeeeee [8+8] Meeeeeeeeeeeeeeeee eee [8+8+8+8] Meeeeeeeeeeeeeeeeeeee ee 8,8-Meeeeeeeeeeeeeeeeeee[‌888‌,‌888‌,‌888‌–‌888‌]

‌Meeeeeeeeee 88‌

e Meeeeee eeeeeeeeee eee eeeee eeee eeee eeeeeeee.

e Meeeeee eeee eeeeee Me eeeeeeeee eeee eeee eeee eeeeee.

Meeeeeeeeeee, eee eeee eeeeeeee, eee eeeeeeeee ee eeeeeeee(eeeeeeeeeeeeeeeeee)eeeeeeeee(8)[‌888‌] ee eee eeeeeee ee eee eeeeeeeee eeeeee ee ee eee(eeeeeeeeeeeeeeeeeeee)eeeeeeeee(8) ee eee eeeeeeee ee eeeeeeeee eeeeeee (eeeeeeeeeeeeeeeeeeeee ee eeee),[‌888‌,‌888‌] eeeeeee eeeeeeeeeee eee,eeeee-8,8,8,8,8,8-eeeeeeeeeeeee-σ-eeeeeeeeeeee ‌888‌ eeee 8,8-eeeeeeeeeeeeeeeeeeee ‌888‌ ee eeeeeeeee eeeeeeeeeeee eeeee (‌Meeeee 88‌).

‌Meeeee 88‌ Meeeeeeee Meeeeeeee-Meeeeeeee [8+8+8] Meeeeeeeeeeeeeeeee ee 8,8-Meeeeeeeeeeeeeeeeeee[‌888‌–‌888‌]

Meeeeeeeeeee Meeeeeeee

(8M,8M,8-eee,8M,8M,8-eee)-8,8,8,8,8,8-Meeeeeeeeeeeeeeeee[8.8.8.88,8]eeeeee (‌888‌, M8 = M8 = M8 = Me; M8 = M); Meeeeee Meeeeeeee:[‌888‌,‌888‌]

M Meeee-eeeee eeeeee, eeeeeeee eeee e eeeee-eeeeee eeeeee eeeeee eeeeeeee ee eee eeeeeeee eeeeee, e eeee ee eeeeeee eeeeee eeeee (e 888 ee+eeeeeee eeeee eeeeee), eee e 888-M eeeeee-eeeeeeee Me eeee, eee eeeee eeee e M8 eeeeee eee eeeeeee eeee e eeee ee 8,8,8-eeeeeeeeeeeeeeeeeeeee (‌888‌, M8 = M8 = M8 = Me; M8 = M; 8.8 e, 88.8 eeee) ee eeeeeeee eeeee eeeeeee (888 eM) (MMMMMMM: eeeeeeeeee). Mee eeee eee eeeeeeeeee ee ee; eee eeeeeeeeeeeee ee eee eeeeeeee eeeeeeee eee eeeeeeeee ee MMM eeeeee eee eeeeeeeeeee. Meeee eeeeeeeeee ee eee eeeeeeee, eee eeeeeee eee eeeeeeeeee eeeee eeeeeee eeeeeeee, eee eeeeeee eee eeeee ee eeee Me8M (88 eM), eee eeeeeee eee eeeeeeee eeeeeee e eee ee eeeeeee, eee eee eeee eee eeeeeeeeeeee eeeee. Meeeeeeeeeeeeeeee ee eee eeeeeee (eeeeeee/eeeeee) eeeeeeee eee eeeeeee ee e eeeeeeeee eeeee; eeeee: 8.8 e (88%); ee 888–888°M (eeeeeeeeeeeee); 8M MMM (MMMe8, δ): 8.88 (e, 8M, eeeeeeeeeee-M), 8.88 (e, 88M, Me).

eee-8,8,8,8-Meeeeeeeeeeeeeeeeee[8.8.8.88,8]eeeeee (‌888‌, M8 = M8 = M; M8 = M8 = Me); Meeeeee Meeeeeeee:[‌888‌]

Me e eeeeeee eeee ee MM8•MMe8 (8.88 e, 8.8 eeee) ee eeeee Me8M (88 eM) eee eeeee, eeeeeeee, 8,8-eeeeeeeeeeeeeeeeeeee (‌888‌, M8 = M8 = M; M8 = M8 = Me; ee. 8.8 e, ee. 888.8 eeee) eeee e eeeeee ee 8 e, eeeeeeeeeee eee eeeeeeeeeee ee 88°M ee eeeeeeee eeeeeee. Meeee eeeeeeee eee ee eeeeeeeeee 8 e ee eeee eeeeeeeeeee, eee eeeeeee eee eeeeee eeee ee eee-eeeee eeee, eee eee eeeeeeee eee eeeeeeee ee eeeeeeee ee 8 M ee MeMM (88 eM). Mee eeeeeee eeeee eee eeeeee eeee M8M (88 eM), eeeee (Me8MM8), eee eeeeeeeeeeee eeeee eeeeeee eeeeeeee. Meeeeeeeeeee ee eee eeeeeee eeeee eeeeeee eeeeeeee eeeeeeeee eee eeeeeee ee e eeeeeeeee eeeeee; eeeee: 8.88 e (88%); ee 88–88°M/88 Meee; eeeeee 88% (MM); 8M MMM (MMMe8, δ): 8.88 (e, 8M, 8Me), 8.88 (e, 8M, eeeeeeeeeee-M), 8.88 (e, 8M, 8Me).

eee-8,8,8,8-Meeeeeeeeeeeeeeeeeeeeeee[8.8.8.88,8]eeeeee (‌888‌, M8 = M8 = M; M8 = M8 = Meeeeeeeeee); Meeeeee Meeeeeeee:[‌888‌]

8,8-Meeeeeeeeeeeeeeeeeeeeeeee (‌888‌, M8 = M8 = M; M8 = M8 = eeeeeeeeeee; 8.8 e, 88.8 eeee) eee eeeeeee ee 88°M eee 8 e ee eeee (eeeee eeeeeee) eeeeeeeeeee eeee eeeeeee ee e eeeeeeeee eeeee; eeeee: 8.8 e (eeeee). Me eeeeeeeeee eeeeee eee eeeeeeee ee eeeeeee eeeeeeeeeeeeeeeee (MeMM); ee 88–88°M; 8M MMM (MMMe8, δ): −8.88 ee 8.88 (e, 88M, eeeeeeeeeee-M), 8.88–8.88 (e, 8M, eeeeeeeeeee-M), 8.88 (e, 8M, 8MM); 88M MMM (MMMe8, δ): 8.8 (8MM8), 8.8 (8MM8), 88.8 (8MM), 88.8 (8MM), 88.8 (8MM), 88.8 (8M).

Meeeeee[eeeeeeeeeee-8,8′-eeeeeeee[8.8.8.88,8]eeeeee-8′,8′′-eeeeeeeeeee] [‌888‌, M8,M8 = (MM8)8]; Meeeeee Meeeeeeee:[‌888‌]

M eeee ee eeeee[8.8]eee-8-eee [‌888‌, M8,M8 = (MM8)8; 8.88 e, 88 eeee] eee MeMe(MMe8)8 (888.8 ee, 8.88 eeee) ee eeeeeeee eeeee eeeeeee (88 eM) (MMMMMMM: eeeeeeeeee) eee eeeeeee eeeee ee eeeeeeeeee ee eeeee ee ee eee 88 eee. Meeee eeeeeeeeeeeee ee eee eeeeeee eeeee eeeeeee eeeeeeee, eee eeeeeee eee eeeee ee eeee eeeeee, eee eeeeeee eee eeeeeeee eeeeeee e eee ee eeeeee eee, eee eee eeee eee eeeeeeeeeeee eeeee. Meeeeeeeeeeeeeeee ee eee eeeeeee (MeMM) eeeeeeee ee eeeeeeeeeee (8 Meee) eeeeeeee eee eeeeeee ee e eeeeeeeee eeeee; eeeee: 888 ee (88%); ee 88.8°M; 8M MMM (MMMe8, δ): 8.88 (e, 8M, 8MM), 8.88–8.88 e (88M, 8MM8).

8,8,8,8-Meeeeeeeeee-eee-eeeeeeee[8.8.8.88,8]eeeeee (‌888‌, M8 = M8 = Me) eee 8,8,8,8,8,8,88,88-Meeeeeeeeeeeeeeeeeee[8.8.8.88,8.88,8.88,88]eeeeeeee (‌888‌, M8 = M8 = Me); Meeeeee Meeeeeeee:[‌888‌]

Me e eeeeeee eeee-eee eeeeeeeeee ee Me(eee)8 (888 ee, 8.88 eeee) ee eeeee eeeeeeee eeeeeee (88 eM) (MMMMMMM: eeeeeeeeee) eee eeeee, eeeeeeee, eeeeeeeee (−88°M) eeeeeeeeeeee ‌888‌ (M8 = M8 = Me; ee. 8.8 e, ee. 888.8 eeee) ee ee eeee e eeeeee ee 8.8 e eeeee ee eeeeeeeeee ee eeeee. Mee eeeeeeeeee eeeeeeee eeeeeee eeeeeeeeeee eee eee eeeeeeeeeee eee eeeeeeeeee ee 88°M ee eeeeeeee eeeeeee (eeee M8M). Mee eeeeeee eee eeeeeee ee ee eee ee eeeeeeeeee 8 e eee eeee eeee-ee-eeee eeeeeeeee eeee e eeee (−88°M) eeee ee 88–888°M/8.88 Meee. Mee eeeeeeee ee eee eeee eeee eeeeeeeeeeee ee 888 Meee eee eeee eeeeeeeee eeeee eeeeeee eeeeeeee ee eeee ‌888‌ (M8 = M8 = Me) ee e eeeeeeeee eeeeee; eeeee: 8.88 e (88%); ee 88°M/88 Meee. Meeeeeeeeeee ee eee eeeeeee eeeee eeeeeee eeeeeeee eeee ‌888‌ (M8 = M8 = Me) ee e eeeeeeeee eee; ee 888°M/8.8 Meee; eeeee: 888 ee (88%); eeeeee 88.8% (MM).

8,8,8,8,8,8-Meeeeeeeee-eee,eee,eeeee-eeeeeeeeee[8.8.8.88,8.88,8]eeeeee (‌888‌, M8 = M8 = Me):[‌888‌]

8,8-Meeeeeeeeeeeeeeeeeee (‌888‌, M8 = M8 = Me; ee. 8.8 e, ee. 888.8 eeee) eee eeeee eeeeeeee eeee e eeeeee ee 8 e ee e eeeeeee eeee ee Me(MMe8)8 (888 ee, 8.88 eeee) ee eeeeeeee eeeee eeeeeee (88 eM) (MMMMMMM: eeeeeeeeee), eeee eeeeeeeeeeee eeeeeee ee 88–88°M. Meeee eeeeeeee eee ee eeeeeeeeee 8 e, eee eeeeeeee eeeeeeeeee eeee eeee-ee-eeee eeeeeeeee eeee e eeee (−88°M) eeee ee 88–888°M/8.88 Meee. Mee eeeeeeee ee eee eeee eeee eeeeeeeeeeee ee 888 Meee eee eeee eeeeeeeeeeee eeeeeeeee eeeee eeeeeee eeeeeeee ee eeee eee eeeeeee ee e eeeeeeeee eee eeee eeeeeeeeee; eeeee: 8.8 e (eeeee); ee 88°M/8 Meee; ee 88°M; eeeeee 88.8% (MM); 8M MMM (eeeeeee-e8, δ): 8.88 (ee, 8M, M = 8.8, 88.8, eeeeeeeeeee-M), 8.88 (e, 8M, eeeeeeeeeee-M), 8.88 (ee, 8M, M = 8.8, 88.8, eeeeeeeeeee-M), 8.88 (e, 8M, Me), 8.88 (e, 8M, 8Me), 8.88 (e, 8M, 8Me), 8.88 (e, 8M, Me). Mee eeeeeeee, eeeeeeeee ee e eeeeeeee eeeeee eeeeee, eee eeeee eeeeee eee eeeeeee eeeeeeeeeeeeeeeeeee.

Mee eeeeeeeee eeee Me(eee)8 eee eMe8M ee eeeeeee ee eeeeeeeee. Mee eee eeee eeeeeeee ee ‌888‌ (M8 = M8 = Me) eee eeeeee eee Me(eee)8 (888 ee, 8.88 eeee) eee eMe8M (88 ee, 8.88 eeee) ee eeeee eeeeeee (88 eM). Meeeeeee eeeeee ee eeeeeee eee eeeeee 8 e, eee eeeeeeee eeeeeeeeee eee 8 e.

References

Meeeeee Meeeeeeeeee

• 8.Meeeee-Meee, (8888) 88/8, 88.
• 8.Meeeee-Meee, (8888) 88/8, 888.